You should try Linux Mint. It’s a good distribution for new Linux users. It’s easy to understand, has a good community with plenty of solutions for all types of problems and it is not too specific.
Gaming with Steam on Linux works without any major issues except when it comes to games that intentionally made run on Windows only due to their DRM. I suggest using the Flatpak variant of Steam so you won’t clutter your system with too many weird dependencies.