Ideally, install Steam with a native package, but if that doesn't exist, the Flatpak is always fine. You can also use Lutris if you want an all-in-one launcher for Steam, GOG, standalone, itch.io, emulators, etc. (and I know Heroic is nice if you need Epic Games)

If you use a newer device, you might want a distro with a newer kernel, but even Debian will work okay for gaming nowadays.

For most games Proton will work OOTB, but you might want to check on forums and ProtonDB for any information regarding specific tweaks for certain games. The only ones that don't work as of yet are because the companies don't want it to work. (plenty anticheat games work on Linux, Big Tech simply decides to revoke that functionality because money talks)

Linux gaming has had huge development over the last few years, it's awesome!

I am moving to Piefed at scallisto@retrofed.com (https://retrofed.com/u/scallisto)