Hey! Glad to see you're interested. To confirm though, steamOS is arch based not debian based. I really wouldn't suggest arch though, it sometimes takes manual intervention to keep working and you should keep up to date with what's going on if you use it. Subscribe to the mailing list, keep up with the community on lemmy, etc.

SteamOS will handle all of that but Arch absolutely will not. If you're ok with a distro that needs some for babysitting arch is a fine thing to use. It's not as bad as some say and it's certainly not "for CS majors or people who know every detail of how a unix like system works" as the other guy states. That's nonesense, and the rest of their comment was filled with misinformation too

Sorry to say but there will be no "one to one" option.

However, the "desktop mode" is something called KDE Plasma and is available on all distributions. Kubuntu is a good option, it's just ubuntu but it looks different. The underlying tech is the same. Personally I'd suggest looking at the KDE linux mint flavour/spin though.

Though I'd stick to ubuntu or a ubuntu based distro, Fedora Kinoite is also a great option for gaming, or nobara with the plasma spin. Both will be more up to date and nobara is made specifically for gaming

Sorry for the info dump, wish you the best