Child support and custody?

I’m not exactly sure if this is the right place to post this but here goes.

I recently separated from my child’s father. We are not legally married. I was a sahm while his dad provided everything else. We had agreed that I would keep him during the week and he would take him weekends. He has been slacking with that and I told him if he was going to be doing that to just leave the baby with me. He got upset and threatened to take me to court and whatnot. My question is how would this whole process be like? I would like to put him on child support and get things done legally. He said that if we go to court it’ll be 50-50 custody and that he won’t have to pay child support. I don’t have the money for a lawyer or anything like that since I haven’t found a job yet. Any advice you guys can give me. To add my son is 15 months old. I am 21 and his dad is 28.