The words pretty and beautiful are used to describe women, and handsome is used to describe a man. There was a time when one could say "a handsome woman," but that is a very old-fashioned thing to say and you do not hear it anymore.

Both pretty and beautiful sound feminine to me and as a man it would be embarrassing to be called either of these, particularly if my other males friends were to hear me being called pretty or beautiful. Pretty and beautiful are fine to describe a woman. Handsome is more suited to describing a man and would not cause embarrassment if I were to be called this. I would not usually refer to a woman as being handsome.

It is certainly possible to say "a beautiful man", and you can see the description used in context if you google "a beautiful man". The description could describe the man physically, or refer to the beauty of his character. However, it would be more likely that a women would use that description, than would a man.