Note: you cannot do this when your keyboard is in ordinary notebook position because the Auto-rotate selection will not be available. However, using the drop-down menu, you can have your screen rotate to 90, 180, or 270 degrees if you want.
If you want to temporarily rotate your Chromebook’s screen 90 degrees while you’re in notebook mode, it’s easy.
Now, each time you press Shift – Ctrl – Refresh, the screen will rotate another 90 degrees.