What happens during tax season when there’s been a separation?

Me and my ex partner have a 3 year old together and we recently left each other. I was a sahm and obviously he was the one that would always file taxes. Next year I won’t be filing them and he will. Should I ask for money for our son or not? Please don’t be rude in the comments, I know it’s the money that he works for and maybe I shouldn’t even ask for any but it’s my first time in a situation like this so I have no clue.