I have been able to play most games fine on Linux mint.
If he plays Minecraft bedrock he can use “Minecraft bedrock launcher” which loads the android version (if you own it on the play store). Minecraft Java works find on Linux, but I prefer bedrock to use a controller.
Some PC games I play in “bottles” which lets you run windows programs.
I also have “heroic games launcher” that lets me play epic games, gog games and Amazon games.
Back when I was on windows I would rename .webp to .jpg (or was it .png, it’s been a long time) and it would open. Now I’m on Linux and it just works.