How to Fix a Sideways Laptop Screen
If your laptop screen appears "sideways," it means your desktop orientation is set incorrectly. The Windows operating system allows you to adjust your screen orientation to display in either "portrait" or "landscape" mode and a sideways screen indicates that you are currently viewing in "portrait" mode." You can fix this by simply adjusting your screen orientation to reflect your desired settings.
Right-click on your desktop.
Click "Screen Resolution."
Click on the "Orientation" drop-down menu.
Click "Apply." Your laptop screen will no longer be sideways.