I want to know a movie name about a guy that was working as professional prostitute and then he fall in love with a girl of his age that was trying to made him quit this profession

You could name the movie: Odd Romance. Or you could also name the movie: My way of falling in love. And if it's like rated R you could call it Love ***.

I think your thinking of pretty woman you just got the genders mixed up

American Gigolo with Richard Gere?