terminating rights

my ex hasn’t been here for me the whole pregnancy really and he messaged me saying it’s not something he can do or wants to be tied to (even though he told me he purposely got me pregnant) i really don’t care regardless if he’s there or not, my baby WILL be loved and taken care of. how could i ask him to terminate his rights?

i don’t want him popping up when he feels “ready” or once my baby is born. i know i have to wait til after my baby is born, but how do i go about that? i know i’ll probably need a lawyer, but is it just signing papers like an easy process? i’m not sure he’d just agree to it. idk he’s really petty and childish and i know even bringing it up the wrong way would set off problems and he’d all of a sudden want to be involved. i’m just asking for your guys experience or advice. i’m really young and i really don’t know what to do.