Two very good questions.
I would define a father as someone who should have no legal say in whether an abortion happens or not, similar to a priest, judge or congressperson. That is not the entire definition but the part relevant to this discussion at the moment.
A father can try to be persuasive within the confines of non abusive non coercive behavior, but the decision should always be between the mother and her doctor.
No abortion, birth, or rearing is ever easy no matter what people tell you.