Check out Proton-Sarek if you have an older GPU for Windows games on Linux
Valve's work with Proton to run Windows games on Linux / Steam Deck is amazing, but they do require you have newer GPUs so some have been a bit left behind. Proton-Sarek aims to fix that.
How to setup OpenMW for modern Morrowind on Linux / SteamOS and Steam Deck
How to install Hollow Knight: Silksong mods on Linux, SteamOS and Steam Deck