To know how to rotate computer screen back to normal mode on Windows, press Ctrl + Alt + Up Arrow. This shortcut restores the default orientation. Alternatively, right-click on the desktop, select Display Settings, and set the Display orientation to "Landscape," then click Apply.
On a Mac, go to System Preferences > Displays, enable the Rotation option, and choose “Standard” or 0° rotation. Confirm the changes to return the screen to normal mode.