How do I find the roots of $y=e^x-2$? I need to find the root of this: $y=e^x-2$.

I don't know how to find the roots of this function because I have two variables...
The teacher said the root is between $0$ and $1$.
When they talk about roots they want those $x$ values which makes $y=0$

So you want to find $x$ such that $$e^x -2 =0$$

That is solving $e^x=2$.

You can solve it by taking the natural logarithm of both sides.
You can solve it algebraically as above. There's also many  numerical approaches. Here's one. 

Let $x_0$=1. 

It can be shown that the sequence,  $x_{n+1}=x_n-\frac{e^{x_n}-2}{e^{x_n}}$, gets closer to the root for higher and higher iterations. 

$x_{n+1}=x_n-1+\frac{2}{e^{x_n}}$