user13375: In this video clip you can see renowned Tibetan master Chögyal Namkhai Norbu saying that life is unreal and that the Buddha taught it is just like a dream. Is he correct? I've transcribed below:

Sometimes we have very nice dream. Fantastic dream... And we enjoy. We
are very happy. We are dreaming, for example... ...I'm looking and
someone is selling... lottery ticket. Very, very big lottery. I am
taking and buying from someone and I am returning home. And I am
seeing the television. And when I am looking at my number... The
television is saying that number! Then I feel very happy. "Oh, what do
I do now?" All this money. I am really happy and then I wake up. When
I wake up, I discovered that is a dream, unfortunately. I am not
happy. Or sometimes... very, very bad dream. There are many people
that want to kill me. They are arriving in my house. Then they are
starting to kill me. I feel very afraid. That moment I wake up. And I
discover, "Oh, that is only a dream!" I am very happy. You see, good
or bad. Even good or bad. A dream is a dream. Unreal. So Buddha is
saying, our life is just like a dream. Big dream. Dream of night is a
very small dream, but... Our life's dream, it has many day and night,
day and night etcetera. When we discover that... Dreams, we discover
when we wake up. But big dreams, we discover... When we are dying and
being in a state of Bardo (transitional state).

Emphasis mine.
A closely related question (with answers) is here.

user17652: It might be possible for you to gain the understanding you need from these two powerful excerpts. The first is from the Phena Sutta; the second is from chapter 32 of the Diamond Sutra.

The Phena Sutta
Form is like a glob of foam;
feeling, a bubble;
perception, a mirage;
fabrications, a banana tree;
consciousness, a magic trick —
this has been taught
by the Kinsman of the Sun.
However you observe them,
appropriately examine them,
they're empty, void
to whoever sees them
appropriately.

[ADDITION]
How can the Phena Sutta be describing something that is dream-like? The aggregates give their fascination over to form-based ideas such that they develop an unhealthy reliance on those ideas. This is called clinging. Clinging presents itself in two ways: attraction and aversion. It is not objects that we cling to, but it originates from our interpretation of those objects; the way in which those objects are cognized. Therefore, the clinging is always from that origin: the mind - the neurotic mind clings to the body. It is this motion of aversion and attraction that creates a noisy haze in our consciousness, stimulated by feeling/perception. This is pananca. This haze hinders our view; we don't see clearly. This not seeing clearly is avijja from which suffering arises. The experience of suffering is a method by which the body tries to eject wrong views born from that very ignorance, but we misperceive its function. Suffering then becomes an identity instead of knowledge. This is how the aggregates can present themselves as dream-like. It's just another way to speak about ignorance. It doesn't matter how you word it. If dream is suitable for you, then fine, as long as you understand the mechanisms behind it.


The Diamond Sutra
“Subhuti, how can one explain this Sutra to others without holding in
mind any arbitrary conception of forms or phenomena or spiritual
truths? It can only be done, Subhuti, by keeping the mind in perfect
tranquility and free from any attachment to appearances.”
“So I say to you – This is how to contemplate our conditioned
existence in this fleeting world:”
“Like a tiny drop of dew, or a bubble floating in a stream; Like a
flash of lightning in a summer cloud, Or a flickering lamp, an
illusion, a phantom, or a dream.”
“So is all conditioned existence to be seen.”
Thus spoke Buddha.


user16635: The point is that when we look out into the world and we see (say) a tree, a dog, a car, a white cloud, or whatever you like, what we're actually perceiving is color, shading, texture, apparent movement... We receive this great wash of ambiguous sensation, and in our heads we establish boundaries, conjure up structures and patterns, intuit relationships, and fit these sensations into concepts, discarding most of the sensations that got us there. We then treat these conceptual objects as though they were part and parcel of the real world, instead of fabrications we impose on the real world after-the-fact.
When we sleep these concepts sometimes float free of any referent and appear to us as dreams, but seeing a dog running in a dream and seeing a dog running in a field is merely a matter of degree. Both have that 'dream-like' quality of a conceptualization that is at best loosely connected to anything material.

user471: The Pali suttas are almost the same as Mahayana agamas in Sanskrit, and so would be on-topic as Mahayana-relevant content.
From Dona Sutta, the Buddha calls himself "awakened":

"Just like a red, blue, or white lotus — born in the water, grown in
the water, rising up above the water — stands unsmeared by the water,
in the same way I — born in the world, grown in the world, having
overcome the world — live unsmeared by the world. Remember me,
brahman, as 'awakened.'

This means he has awakened from a dream of course.
Awakening from the dream does not mean that the world is a dream or that the world is unreal.
It's because the dreamer (the self) is unreal, as the Buddha taught that all phenomena is not self (sabbe dhamma anatta - Dhp 279).
Upon waking from the dream, the dreamer disappears in this case. Also all reification/ objectification-classification/ papanca arising from the self - non-self duality is the dream that disappears.
The chair however doesn't disappear and the Buddha can still sit on it.
From Vina Sutta:

"In the same way, a monk investigates form, however far form may go.
He investigates feeling... perception... fabrications...
consciousness, however far consciousness may go. As he is
investigating form... feeling... perception... fabrications...
consciousness, however far consciousness may go, any thoughts of 'me'
or 'mine' or 'I am' do not occur to him."

From Tuvataka Sutta:

"I ask the kinsman of the Sun, the great seer,
about seclusion & the state of peace.
Seeing in what way is a monk unbound,
clinging to nothing in the world?"
"He should put an entire stop
to the root of objectification-classifications:
'I am the thinker.'

The translator commented:

On objectification-classifications and their role in leading to
conflict, see Sn 4.11 and the introduction to MN 18. The perception,
"I am the thinker" lies at the root of these classifications in that
it reads into the immediate present a set of distinctions — I/not-I;
being/not-being; thinker/thought; identity/non-identity — that then
can proliferate into mental and physical conflict. The conceit
inherent in this perception thus forms a fetter on the mind. To become
unbound, one must learn to examine these distinctions — which we all
take for granted — to see that they are simply assumptions that are
not inherent in experience, and that we would be better off to be able
to drop them.


13375: <p>In this <a href="https://www.pbs.org/video/pov-my-reincarnation-dreams-deleted-scene/" rel="nofollow noreferrer">video clip</a> you can see renowned Tibetan master <a href="https://en.wikipedia.org/wiki/Namkhai_Norbu" rel="nofollow noreferrer">Chögyal Namkhai Norbu</a> saying that life is unreal and that the Buddha taught it is just like a dream. Is he correct? I've transcribed below:</p>
<blockquote>
<p>Sometimes we have very nice dream. Fantastic dream... And we enjoy. We
are very happy. We are dreaming, for example... ...I'm looking and
someone is selling... lottery ticket. Very, very big lottery. I am
taking and buying from someone and I am returning home. And I am
seeing the television. And when I am looking at my number... The
television is saying that number! Then I feel very happy. &quot;Oh, what do
I do now?&quot; All this money. I am really happy and then I wake up. When
I wake up, I discovered that is a dream, unfortunately. I am not
happy. Or sometimes... very, very bad dream. There are many people
that want to kill me. They are arriving in my house. Then they are
starting to kill me. I feel very afraid. That moment I wake up. And I
discover, &quot;Oh, that is only a dream!&quot; I am very happy. <strong>You see, good
or bad. Even good or bad. A dream is a dream. Unreal. So Buddha is
saying, our life is just like a dream. Big dream.</strong> Dream of night is a
very small dream, but... Our life's dream, it has many day and night,
day and night etcetera. When we discover that... Dreams, we discover
when we wake up. But big dreams, we discover... When we are dying and
being in a state of Bardo (transitional state).</p>
</blockquote>
<p>Emphasis mine.</p>
<p><a href="https://buddhism.stackexchange.com/questions/29003/mahayana-doctrine-about-dreams-and-illusions">A closely related question (with answers) is here.</a></p>
 17652: <p>It might be possible for you to gain the understanding you need from these two powerful excerpts. The first is from the Phena Sutta; the second is from chapter 32 of the Diamond Sutra.</p>
<blockquote>
<p><a href="https://www.accesstoinsight.org/tipitaka/sn/sn22/sn22.095.than.html" rel="nofollow noreferrer">The Phena Sutta</a></p>
<p>Form is like a glob of foam;
feeling, a bubble;
perception, a mirage;
fabrications, a banana tree;
consciousness, a magic trick —
this has been taught
by the Kinsman of the Sun.
However you observe them,
appropriately examine them,
they're empty, void
to whoever sees them
appropriately.</p>
</blockquote>
<p>[ADDITION]
How can the Phena Sutta be describing something that is dream-like? The aggregates give their fascination over to form-based ideas such that they develop an unhealthy reliance on those ideas. This is called clinging. Clinging presents itself in two ways: attraction and aversion. It is not objects that we cling to, but it originates from our interpretation of those objects; the way in which those objects are cognized. Therefore, the clinging is always from that origin: the mind - the neurotic mind clings to the body. It is this motion of aversion and attraction that creates a noisy haze in our consciousness, stimulated by feeling/perception. This is pananca. This haze hinders our view; we don't see clearly. This <em>not seeing clearly</em> is avijja from which suffering arises. The experience of suffering is a method by which the body tries to eject wrong views born from that very ignorance, but we misperceive its function. Suffering then becomes an identity instead of knowledge. This is how the aggregates can present themselves as dream-like. It's just another way to speak about ignorance. It doesn't matter how you word it. If <em>dream</em> is suitable for you, then fine, as long as you understand the mechanisms behind it.</p>
<hr />
<blockquote>
<p><a href="https://diamond-sutra.com/read-the-diamond-sutra-here/diamond-sutra-chapter-32/" rel="nofollow noreferrer">The Diamond Sutra</a></p>
<p>“Subhuti, how can one explain this Sutra to others without holding in
mind any arbitrary conception of forms or phenomena or spiritual
truths? It can only be done, Subhuti, by keeping the mind in perfect
tranquility and free from any attachment to appearances.”</p>
<p>“So I say to you – This is how to contemplate our conditioned
existence in this fleeting world:”</p>
<p><em>“Like a tiny drop of dew, or a bubble floating in a stream; Like a
flash of lightning in a summer cloud, Or a flickering lamp, an
illusion, a phantom, or a dream.”</em></p>
<p><em>“So is all conditioned existence to be seen.”</em></p>
<p>Thus spoke Buddha.</p>
</blockquote>
 16635: <p>The point is that when we look out into the world and we see (say) a tree, a dog, a car, a white cloud, or whatever you like, what we're <em>actually</em> perceiving is color, shading, texture, apparent movement... We receive this great wash of ambiguous sensation, and in our heads we establish boundaries, conjure up structures and patterns, intuit relationships, and fit these sensations into concepts, discarding most of the sensations that got us there. We then treat these conceptual objects as though they were part and parcel of the real world, instead of fabrications we impose on the real world after-the-fact.</p>
<p>When we sleep these concepts sometimes float free of any referent and appear to us as dreams, but seeing a dog running in a dream and seeing a dog running in a field is merely a matter of degree. Both have that 'dream-like' quality of a conceptualization that is at best loosely connected to anything material.</p>
 471: <p>The Pali suttas are almost the same as Mahayana agamas in Sanskrit, and so would be on-topic as Mahayana-relevant content.</p>
<p>From <a href="https://www.accesstoinsight.org/tipitaka/an/an04/an04.036.than.html" rel="nofollow noreferrer">Dona Sutta</a>, the Buddha calls himself &quot;awakened&quot;:</p>
<blockquote>
<p>&quot;Just like a red, blue, or white lotus — born in the water, grown in
the water, rising up above the water — stands unsmeared by the water,
in the same way I — born in the world, grown in the world, having
overcome the world — live unsmeared by the world. Remember me,
brahman, as 'awakened.'</p>
</blockquote>
<p>This means he has awakened from a dream of course.</p>
<p>Awakening from the dream does not mean that the world is a dream or that the world is unreal.</p>
<p>It's because the dreamer (the self) is unreal, as the Buddha taught that all phenomena is not self (<em>sabbe dhamma anatta</em> - <a href="https://www.accesstoinsight.org/tipitaka/kn/dhp/dhp.20.budd.html" rel="nofollow noreferrer">Dhp 279</a>).</p>
<p>Upon waking from the dream, the dreamer disappears in this case. Also all reification/ objectification-classification/ <em>papanca</em> arising from the self - non-self duality is the dream that disappears.</p>
<p>The chair however doesn't disappear and the Buddha can still sit on it.</p>
<p>From <a href="https://www.accesstoinsight.org/tipitaka/sn/sn35/sn35.205.than.html" rel="nofollow noreferrer">Vina Sutta</a>:</p>
<blockquote>
<p>&quot;In the same way, a monk investigates form, however far form may go.
He investigates feeling... perception... fabrications...
consciousness, however far consciousness may go. As he is
investigating form... feeling... perception... fabrications...
consciousness, however far consciousness may go, any thoughts of 'me'
or 'mine' or 'I am' do not occur to him.&quot;</p>
</blockquote>
<p>From <a href="https://www.accesstoinsight.org/tipitaka/kn/snp/snp.4.14.than.html" rel="nofollow noreferrer">Tuvataka Sutta</a>:</p>
<blockquote>
<p>&quot;I ask the kinsman of the Sun, the great seer,<br />
about seclusion &amp; the state of peace.<br />
Seeing in what way is a monk unbound,<br />
clinging to nothing in the world?&quot;<br />
&quot;He should put an entire stop<br />
to the root of objectification-classifications:<br />
'I am the thinker.'</p>
</blockquote>
<p>The translator commented:</p>
<blockquote>
<p>On objectification-classifications and their role in leading to
conflict, see <a href="https://www.accesstoinsight.org/tipitaka/kn/snp/snp.4.11.than.html" rel="nofollow noreferrer">Sn 4.11</a> and the introduction to <a href="https://www.accesstoinsight.org/tipitaka/mn/mn.018.than.html" rel="nofollow noreferrer">MN 18</a>. The perception,
&quot;I am the thinker&quot; lies at the root of these classifications in that
it reads into the immediate present a set of distinctions — I/not-I;
being/not-being; thinker/thought; identity/non-identity — that then
can proliferate into mental and physical conflict. The conceit
inherent in this perception thus forms a fetter on the mind. To become
unbound, one must learn to examine these distinctions — which we all
take for granted — to see that they are simply assumptions that are
not inherent in experience, and that we would be better off to be able
to drop them.</p>
</blockquote>
