How do I befriend people I think look nice?

I just joined a martial arts club because I wanted to keep myself busy during the summer, but also because I wanted to make new friends (my friendship circle mainly keep to themselves during the holidays). There are a few people there who I think look really nice/cool/interesting? But I’m not sure how to befriend/approach them because I’m scared they might not reciprocate the feeling. Any advice would be appreciated! <3