How do I change the owner on an iPad?

If you mean set it up for a different user, you need to restore it to factory condition, they then can set it up with their own Apple ID and password. This process will erase everything on the iPad.

What to do before selling or giving away your iPhone, iPad, or iPod touch:

https://support.apple.com/en-us/HT201351

If you simply want to start again as a new user, you’d need to back up the device to iCloud.

You can then reset the device and when you start up, set it up under your iCloud account.