My dad has mental illness and is mentally abusive and it’s just not in my best interest to be around him. This has been going on my entire life. He’s 78 and gets around very well. He’s just crazy and I cannot handle it.
what are my legal responsibilities with being POA. I don’t want this.
Consent doesn't need to be given to be appointed as POA. However as others have pointed out one needs to accept the appointment. You will simply decline to serve. Most documents will name a successor in the event the appointed person is unwilling or unable to serve.
As to what your responsibilities as POA would be managing finances if he is unable, signing documents, and potentially making health care decisions if you are also named as health proxy.
Good for you for recognizing its not healthy for you to be around him and nipping that in the bud. And don't let anyone pressure you later with "but there's no one else"... There's always someone else even if that person is appointed by the state..
Do know that this document being around, unknown to anyone, doesn't much matter until someone fishes it out of a drawer. Then you can say you refuse to serve.