If you like to see beautiful women, go to the gym to work out.
I don't think this boy is worth your pain to lose weight for him. If he likes you, it has nothing to do with whether you are fat or not. You are too fat or too thin, no matter what, it will not make him move. So now you can work hard, study hard, make money, nourish yourself, constantly improve your charm, live a rainy life, meet better boys who like you at any time, and completely change yourself!