It doesn't sound like you have direct access to your SSDI. Some people don't. and there is a payee who gets their money and supervises their access to it. I don't know if that is your situation. But it sounds like your father has some control like that. That could be because you are a minor or for other reasons.

If you have problems handling your own money, then a family member might be court-appointed to help you. It could be your father. If you get married, it could be your spouse. Courts try to act in your interest.