So sorry Black Wolf that you are going through this. As a son, and almost 18, I'm sure your Dad is feeling pressure within himself that you need to be baptised to make him look good.
Alas, sometimes as parents we THINK we are doing something for the benefit of our children, but in fact it is for OUR benefit. I feel this is the case, he just wants to look good in front of the congregation. He has anger issues because he feels he looks bad .....
But that is HIS problem. You shouldn't get baptised and shouldn't feel pressured. Of course, you do feel pressured. I am hoping you have a plan when you turn 18 (and PLEASE may it include higher education!!!!!)
The truth of the matter is there's not much you can do to ease your Dad's discomfort, but in the end, you can't mess up your life to make him feel better.
Do whatever you need to do to survive in some comfort until you can be independent. Your Dad may come around in time, but he may not. But, as I said, it's his problem not yours.
I am a mother and when Son of Spiral said "No way!" it woke me up (totally). Perhaps it will happen that way with your parent(s). I really hope so, but your choice is YOUR choice.