Baby's last name

Georganna • 21. First baby due Feb 12th. Pittsburgh.
I can't decide if I want the baby to have my last name or the dads. We are not together, broke up about a week before I found out I was pregnant because all we did was argue. It's no different now. I'm 16 weeks. He hasn't been to any of the 3 appts I had already. When I tell him how I feel or what I'm going through all he says is ok. He owes me money and keeps saying he's not paying me back. He wants the baby to have his last name because he has an 8 year old son that he has no rights too. He told ne I can try to get child support but I won't get any and he's gonna laugh about it. He wants to be in the room during delivery but all he does is talk down to me and argue so I feel like he's going to ruin my day. I'm trying to do what's right for the baby but it's so hard to tell if he's going to be involved. Idk what to do. I thought maybe give the baby his last name but dont put him on the birth certificate but idk it's so much to think about it. Any advice?