What should I do?

The father of my baby and I aren't together. Baby is due August 8th so I have to make a choice on what last name I want to give him but I don't know which one. I would like to give my baby his dad's last name but I've heard that when you do that you can't leave the country without the fathers permission and this guy is such an asshole he would probably not give me permission to take the baby out in the future for vacation. Is this true? Should I get a lawyer? Also he hasn't.  given the baby or me anything this whole time so he doesn't even really deserve it anyways but I'm more concerned about the legal part of this what problems will this cause me. Does anybody know? Any opinions? 
Edit: it is dumb of me to even consider it but idk I guess like always I was just concerned with his feelings. I wanted to think maybe he'll come around and change but now I see he doesn't even deserve that priveledge. It'll just cause me problems