I'm so bad at flirting!!

Hey guys so I'm in this boxing class and there is this man who is REALLY hot. I've spoke with him a few times and he really is a nice, intelligent and interesting person. I'm a bit younger than him and not very good looking (quite a bit of acne, a little bit over weight, except that I have a nice butt 🤷🏼‍♀️) and I'm sure he wouldn't be interested in me because he really loves sport, he is in the army and me on the other hand I struggle so much with healthy things and activity because I'm asthmatic and obviously there are very good looking women that are way better than me at this class. So what would you suggest me to do to seduce or make him understand that I'm into him? I can't really fight with him cause he is way better than me so please give me your advices, and tbh I'm too shy to speak with him except talking about boxing haha