Remove another Apple ID
How do remove someone’s Apple ID content from my phone
iPhone 14 Pro Max, iOS 16
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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.