Child support question...

I want to put my ex on it so that he can help financially take care of what he helped make. He thinks it’s unfair bc he will only be seeing our son once a week (he works ft and is in law school in the fall) bc he’s so busy...

how does it work if I want to get him on child support but he wants to walk away as a parent?

If he gives up his rights does that mean I get no help from him at all then?