I think you can only make a game needs a Linux build.
Build your game so that it runs on desktop Linux.
Yes you need a Linux build
But yeah need a Linux version of the game but if you are using something like unity it is pretty easy to generate a Linux build even if you are building on Windows.
What if your game runs through Proton? :)
If it runs on linux, it runs on linux
Ok any game that has a Linux build.