All I'm saying is that I would like to change her last name to mine. The rest I'll deal with later. If I can't do it now without his consent. I heard about the step-parent adoption thing. Would I be able to do that later without his consent when I'm married to someone else?
No.

He is the father. Whether he ever is granted custody/visitation rights or not, anything you try to do to remove him as the father from the child's life will have to have his consent. (unless you want to start a very long, expensive, and potentially unsuccessful court battle to have his rights terminated by a court of law).

In short, you chose to have a baby with this man. He is the father and will remain so.

Just another view point on the child support. It is the CHILD'S right to be supported by both parents. It doesn't matter if wants to support her or not.