iPad screen doesn’t rotate

Did you turn off rotation lock in the iOS Control Center?

You invoke the iOS Control Center by swiping a finger downward from, approx., the top right corner of your iPad.

Look for a button/icon with a padlock symbol inside of it.

If the button/icon is white with a red colored padlock symbol, your iPad's screen rotation is locked.

Tap this padlock button/icon to release the screen lock.

Best of Luck to You!

Ensure that the Screen Rotation Lock is not enabled. Swipe downwards from the extreme top right-hand corner to expose the Control Centre:

Rotate the screen on your iPad