I am trying to switch my sons number to his dads old phone but his screen is broke so cant do it online and don't know the number to call to talk to a live person to get help
Call 800-922-0204, choose option 4, then say "Agent" to get connected to a live person.
You'll need the account passcode (last 4 of the owners SSN, perhaps?) or proof that you are the account owner or authorized to make changes.