It doesn’t really matter what he wants. If you want to end the relationship, end the relationship. He doesn’t have to agree.
He’s sending you all that narcissist stuff becuase he is one and they like to reverse it on others. I’d bet my ass someone told him what he was in the past so now he uses it against others.
Just text dump him and tell him if he wants to see the kid that can be arranged but you won’t be there. Have your parents drop the child off or his mum collect it or whatever works for you. You don’t owe him time, attention or heartache.
No means no, over means over. Block him on everything apart from one phone and get a new phone for everything else so that you don’t need to check that phone often.
Don’t agree to communicate by phone all or in person. “It’s over. Do not contact me again. Child arrangements can be sorted out via my solicitor\our family”. If he texts any abuse or threats or turns up outside then report him to the police. Don’t reply to anything from him unless it’s about the kid.
He will try to goad you. Don’t respond to his messages straight away if you feel a knee jerk reaction coming on. Instead, put the phone in a drawer for an hour and go decompress.
You're going to have to have strong boundaries with yourself, not just with him.
Be cold. It’s ok to be cold to protect yourself. Don’t try and compromise with him going forwards with anything that doesn’t suit you because his sort take compromise as weakness and they attack weakness.
Pick up a book about how to coparent with a narcissist.