Press the Steam button and the “…” button a couple times together and it’ll launch Big Picture mode, will feel just like Steam OS. This was the “a-ha” moment that convinced my roommate that Windows was the way to go.

Gaming mode is part of steam os, but since u already change your os to windows, so there will be no gaming mode. U can only use steam app

Typical windows user inquiry.

I’m going to give you the benefit of the doubt and assume you didn’t understand that “Gaming mode” and “SteamOS” are the same thing.

When you wiped out the steamos partition, you cannot use the feature of SteamOS which is “gaming mode”.

If you want to use something *similar*: When you boot into windows, you can launch steam in big picture mode. Most of the features including fps caps, decky, etc will not be available, as they are tied to gaming mode, thus SteamOS.

You installed a different OS. If you want to go back, reinstall SteamOS. If you Google “reinstall Steam OS Steam Deck” there are a ton of instructions.