As per Microsoft, Tablet mode in Windows 11 is removed and new functionality and capability are included for keyboard attach and detach postures.
So to turn off Tablet mode, physically convert the tablet back into a laptop by reattaching the keyboard or rotating the screen back into a laptop orientation.
But in your case, you can do this by editing the registry but make sure you have created a restore point or backup of the registry.
-Navigate to the following key in the Registry Editor:
-In the right pane, you should see a DWORD value named TabletMode. In order to turn off tablet mode, double-click on TabletMode and set it to 0. Or set it to 1 if you want to turn on tablet mode.
Hope this resolves your Query !!
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