Remove another Apple ID
How do remove someone’s Apple ID content from my phone
iPhone 14 Pro Max, iOS 16
Question marked as
They should have done this before giving you the device: What to do before you sell, give away, or trade in your iPhone or iPad - Apple Support
You can do most of it yourself too. If you don't want to do an entire erase of the device then you'll have to hand-pick things to be deleted. Just make sure that Find My is deactivated for the other ID or else you'll run into major trouble at some stage.