user113546: I have two paper wallets and want to transfer 10 bitcoins between them. I do not want to use any other 3rd party software or hard wallet because they're created by individuals, so they can access my data if they try hard enough. And no exchanges, for the same reason.
Once I enter my private key anywhere but receiver side, it gets stolen. So naturally I have a question, how, if regardless of the way someone is involved?
Please correct me if I misunderstand something.

user-1: Use bitcoin core: https://bitcoincore.org/en/download/
If interested to review and compile yourself, follow the instructions mentioned here: https://jonatack.github.io/articles/how-to-compile-bitcoin-core-and-run-the-tests

user43221: You can do it manually with highly secure way:

Get UTXO's of coins that you want to transfer (TX Hash, Value in Satoshi and No of output).
Form the unsigned transaction using outputs from the previous paragraph as inputs to your's new receiving address. Remember that the value of new outputs must be less than summary value of inputs on the estimated fee rates.
Get sha256 from unsigned TX.
Calculate signatures for each spending output.
Form signed TX.
Send TX to nodes, for example using this service or directly send raw tcp packet to your known nodes.

If you need, I may explain this process with more details.

user38618: No matter which wallet you use, use one with offline transaction functionality. That's what you need.
Use Electrum offline: https://electrum.readthedocs.io/en/latest/coldstorage.html?highlight=usb
You need two Electrums. You can use the watch-only one on your daily computer, and the air-gapped one on one Tails Linux burned CD.
You may instead generate a raw transaction and sign it using Core as Prayank suggested but Bitcoin Core, if it hasn't changed recently, needs hours of sync before you can act.

user26873: If you want to avoid all third parties, you need to run a node yourself. Download bitcoin-core and let it sync might take a day or two depending on your machine.
You can import your paper wallet by taking the WIF private key and using the importprivkey command in the bitcoin console. Note the rescan will take a while, but once it is done you can spend to any address you like.

113546: <p>I have two paper wallets and want to transfer 10 bitcoins between them. I do not want to use any other 3rd party software or hard wallet because they're created by individuals, so they can access my data if they try hard enough. And no exchanges, for the same reason.</p>
<p>Once I enter my private key anywhere but receiver side, it gets stolen. So naturally I have a question, <em>how</em>, if regardless of the way someone is involved?</p>
<p>Please correct me if I misunderstand something.</p>
 -1: <p>Use bitcoin core: <a href="https://bitcoincore.org/en/download/" rel="nofollow noreferrer">https://bitcoincore.org/en/download/</a></p>
<p>If interested to review and compile yourself, follow the instructions mentioned here: <a href="https://jonatack.github.io/articles/how-to-compile-bitcoin-core-and-run-the-tests" rel="nofollow noreferrer">https://jonatack.github.io/articles/how-to-compile-bitcoin-core-and-run-the-tests</a></p>
 43221: <p>You can do it manually with highly secure way:</p>
<ol>
<li>Get UTXO's of coins that you want to transfer (TX Hash, Value in Satoshi and No of output).</li>
<li>Form the unsigned transaction using outputs from the previous paragraph as inputs to your's new receiving address. Remember that the value of new outputs must be less than summary value of inputs on the estimated fee rates.</li>
<li>Get sha256 from unsigned TX.</li>
<li>Calculate signatures for each spending output.</li>
<li>Form signed TX.</li>
<li>Send TX to nodes, for example using <a href="https://www.blockchain.com/btc/pushtx" rel="nofollow noreferrer">this</a> service or directly send raw tcp packet to your known nodes.</li>
</ol>
<p>If you need, I may explain this process with more details.</p>
 38618: <p>No matter which wallet you use, use one <strong>with offline transaction functionality</strong>. That's what you need.</p>
<p>Use Electrum offline: <a href="https://electrum.readthedocs.io/en/latest/coldstorage.html?highlight=usb" rel="noreferrer">https://electrum.readthedocs.io/en/latest/coldstorage.html?highlight=usb</a></p>
<p>You need two Electrums. You can use the watch-only one on your daily computer, and the air-gapped one on one Tails Linux burned CD.</p>
<p>You may instead generate a raw transaction and sign it using Core as Prayank suggested but Bitcoin Core, if it hasn't changed recently, needs hours of sync before you can act.</p>
 26873: <p>If you want to avoid all third parties, you need to run a node yourself. Download bitcoin-core and let it sync might take a day or two depending on your machine.</p>
<p>You can import your paper wallet by taking the WIF private key and using the <code>importprivkey</code> command in the bitcoin console. Note the rescan will take a while, but once it is done you can spend to any address you like.</p>
