Made my father switch to Linux about a year ago, so far he loves it. He has the tech knowledge of an oyster, but so far it worked.

Sure I had some convincing to do at first, but once he realized KDE is basically Windows well done without pesky ads, he was sold.

I still have to do some work from time to time (usually through Rustdesk), but globally it works well.

I have to admit my way of doing this was a bit underhanded (steps bellow), but it worked.

1. Move his docs outside of the computer to a NAS. Like that no risk of loosing files. He believed for a long time files were bound to the OS (despire using OpenOffice and Libreoffice for decades), so he through that .odt made on Windows wouldn't be compatible with LibreOffice on Linux.
2. Once W10 support had ended, didn't told him about the extension (I'm a sneaky bastard), and offered to dual boot Linux.
3. Fumble the dualboot (oops, my bad, guess you have to use Linux for the time being, I don't have enough time to reinstall Windows 10). Who knows, maybe intentionally 😆
4. Let him marinate about two weeks, forcing him to try Linux, helping him through Rustdesk when needed
5. When I came back, he asked me if I could install Linux on his laptop. This time I did not fumble the dual boot, but still let Linux be the default boot option

Fast forward almost a year, he didn't boot Windows for at least 6 months, and is pretty happy how snappy Linux is (despite how weak is computer is, he has an Athlon 3000G, paid like fifty bucks years ago, new, with 4GB of RAM, recently upgraded to 8GB with old stock I had around).