Thanks for reply,
Yes when I say 2 devices I mean 1 phone having the app Airgap vault which does have the private key.
The other phone would have the Airgap Wallet installed which would send the transaction by QR code and then I sign it with the airgapped phone (airgap vault app).
1 question here (maybe very stupid question for you but I cant find a logic answer in my mind): I downloaded the app and right after that I went in airplane mode . After being in Airplane mode I configured the Airgap Vault on the phone and received the 24 words seed phrase along with the recovery key and I also created my cryptocoins addresses. Now my questions is , since I ve done all of this completely offline how will the blockchain know about my address and private key? I don't understand how something that was created on an airgapped device completely out of the world can be a part of the blockchain which only exists online, I think . Now I am afraid to send the money to that address because I don't know if it should've been done while I was still online or the way I did it was the right way to do it.
I want to mention that for security I reset the phone to factory and connected it to a safe network to be sure there is no malware.

About the airgap pc , I've read that when you send the transaction to the airgap pc you can also have the malware that's why would be better to use unwritable usb or cd's and destroy after every use. But if the malware is there it can send information through various ways: Electromagnetic,Acoustic,Thermal,Optical. What can it be done to be secured 100% against these methods in the case you take the malware .

My concern is that trough these methods they can take maybe more easily the private key from a phone. Or maybe not because you don't have to send the transaction physically therefore there is no possibility for malware infestation unless it was there before first setup. Am I right? In this case 2 phones using qr codes would make it safer than an airgapped pc?

My last question is , if I use the phone as an Airgapped device should I try to destroy bluetooth/wifi/antennas hardware (if there is any way) or is it safe to leave it as it is? I don't know if there is a way for the hacker to disable my airplane mode and making my phone go online to steal my private key.

Sorry if I sound too dumb but I am a very curious person and also want to have the best security possible. I also do have friends that use crypto and sometimes they rely on my advices as they are more novice than me and I want to be able to give them the best solutions to keep their money safe. \

Thank you very much for your time!