https://help.steampowered.com/en/faqs/view/6121-ECCD-D643-BAA8

“While Steam Deck is fully capable of dual-boot, the SteamOS installer that provides a dual-boot wizard isn’t ready yet. This will ship alongside SteamOS 3 once it’s complete.”

SteamOS 3 is out but im seeing reports its not possible still so…?

TLDR I’m looking for a Steam Deck for both SteamOS gaming but also there are some games not support such as League of Legends and Genshin Impact which I’d like to be able to play with no risk of getting banned, aka just dual boot Windows.