Good Lord; call 1-800-772-1213, 7 am - 7 pm, Monday through Friday (except holidays), and do it from the comfort of your home. Even if you're on hold a while, that's much better than spending money on gas while dodging drivers on their phones, and being in a jammed waiting room during flu season.
You can help your father with the bank information, but they'll have to talk to him first to get some identifying information to protect his privacy.
You can also call your local office if you prefer; look up their number at socialsecurity.gov. While there, look into setting up a private account so you can change the account numbers yourself.
It's recommended that you set up an account anyway (whether you get SSA benefits or not), since your password will keep any scammers from setting up an account under your name. Scammers have it made today with social media "I'm 55 today!" -there's your date of birth, and I guess your name is out there too.
Happy Veterans Day.
