Valve made a compatibility layer for the Steam Deck and Linux called Proton. It uses a lot of technologies, including WINE, dxvk, and more to make Windows games run well on Linux. It basically takes Windows API calls and translates them to Linux with little to no performance penalty.
Steam also has native builds for Windows, macOS, ChromeOS, and Linux now, so you can just install it. Most Linux distros have Steam right in their software manager now.
Typically, unless the game has blocked Linux with something like kernel-level anticheat, it’ll “just work” on Linux now. There is a community database called ProtonDB that has a list of games and how well they do or don’t work.
Hope this helps and feel free to ask any questions.
Check Proton DB. If the games you enjoy work fine on Linux, which is the case for most games these days thanks to Proton, you should be good. The big exception is games with kernel-level anticheat.
If not, you can always dual boot for the few games that don’t.
I made the switch to pure Linux gaming when I got my Steam Deck two years ago. Been loving it ever since. Even SteamVR games work great streaming to my Quest headset.