Free (without activation keys) program for recording video from the screen for training lessons?

Question

Video capture

I want to do programming lessons and upload to YouTube. You need a program that records video from the screen. Recommend something.
It is important that the program:
1) be free, without any activation keys, downloaded and installed
2) as simple as possible to use, the fewer buttons the better
3) the recording quality was normal, 4k of course is not needed, the main thing is that the picture is more or less clear
Please provide a download link if possible.

Answer 1

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