I can tell you that being sexually attracted to an actor is not a necessary condition for determining one's sexual orientation. Say, I am clearly straight and have never been sexually attracted to any male actor.

I do not know whether being sexually attracted to an actor of the same sex is a sufficient condition to say that you are homosexual, but I do know that it is not necessary.

Wanting to be as handsome as somebody does not seem to have any relationship to the issue of sexual orientation.

While I personally have always been straight, since way before puberty, I have read a lot about people who do not figure out their orientation until much later in life. In other words, you do not have a deadline.