Last name help

My last name is corns.. baby’s dad is Forster. We was together 7months before pregnancy and split before I took a test. He didn’t want to be part of baby’s life even after an ultrasound was sent.. until his mum was in contact then I’d get the occasional ‘are u ok’. We always argue and he deals drugs and smokes them in his house. CAn I really trust him with my daughter going off his attitude? Also his mums always going on holidays and I don’t want her to take my daughter until she’s old enough. Which last name should I give my daughter😬