You must know for what reasons you father don't like you BF or crush, here some example : 1. Maybe you are to young for dating, 2. Maybe your crush is bad boy, 3. maybe your father have bad experienced with your crush. If Number 1, just be a friend or best friend, try to not going to far away from relationship cause it will make your father disappointed or even more hate your crush. Number 2, your bf must change and prove to your father that he is trustworthy.
Hakuna^_^matata