For various reasons you may want to rotate your tablet to use it in a different orientation.
Most drawing tablets support these rotations:
Some support all four orientations
Some only support two orientations
Some support only a single orientation
Configure the driver app to perform the rotation
If you have a pen display
ensure you are extending the desktop to the pen display, not duplicating it
In the system's display settings, rotate the the the desktop on the pen display
Physically rotate the tablet
You can perform these steps in any order.
Here is a demonstration of how to rotate a pen display: https://youtu.be/_OkANovOxBQ
Note that not all Wacom tablets have an Orientation option.