Custody HELP!!!

I need serious advice and tips I’m (24) a soon to be dad with a woman (19) who is causing pure hell. Me and her family don’t get along at all. The baby is currently unborn but is due in July and she is already sending me text messages about not being a part of the child’s life. Her family want me completely removed and it seems like they have got into her head. Her idea is since I’m not with her I shouldn’t be in the child’s life. I’m currently a college student and disabled vet who lives and survives on my own does anyone have any type of advice of how I should conduct myself in order to get half or full custody. I really want full custody because she is very immature and has no emotional intelligence. I’m in Florida [FL] btw Any and everything helps!

Edit:

And to make it clear no one slept with a teenager willingly she lied about her age being 22 until she got pregnant so stop the judging nonsense