New iPhone, CHILD MODE selected by mistake, how to proceed or reset from this point so we can finish setup for my 89 year old Pop.

Dad bought a new iPhone 16e and when setting it up the first time, selected CHILD MODE during the process. Does NOT appear that any family has been connected and no AppleID created so far. Now I come along to help him finish setting things up and I can't figure out how to "undo" the CHILD MODE setting. He's very much an ADULT, but I can't figure out how to get anywhere on the phone to set his age to an accurate setting of 89 years old, nor can I figure out how to use my iPhone to become his parent/guardian to help finish setting things up.

Looking either for an answer on HOW to undo the CHILD MODE partial setup (we don't have an Apple ID on the phone yet so we can't install any apps), or HOW to reset the phone to factory settings without an Apple ID or password.