There’s tons of youtube videos / tutorials on how to create a live usb of a distro, such as linux mint. This will allow you to boot into linux and play around without installing anything and get a feel for linux. It’s nowhere as tech wizardry as you think.

And if all your games are on steam and don’t have anti cheat things, they’ll probably just all work with proton (linux compatibility tool in steam).

Nuphy? I don’t know if it meets all your needs but maybe nuphy air 96. Works with VIA and they sell shine through keycaps.