How and should I tell my child's father I'll be baptizing our child into the Catholic Church?

Many Christian religions like to think they are so different than the Catholic faith but Catholicism is Christian. It is a personal decision. I think it is wonderful that you are raising your children and going to m. It is really up to you if you tell dad. If he has a problem with it then he can fly over once a month and take him to his church. Best of luck!