Maybe if you find it hard in general to talk so openly with girls, then maybe start small. Find someone that shares similar likes with you. Maybe start off with cadets or sports seeing as those are times where you socialise. It seems more likely that you’d find a girl there seeing as you share something with them.
If you do cadets in a mixed group then start small talk with a girl you may like. Just a little banter and jokes to diffuse any awkwardness from the introductions and do it in a relaxed way. That way you’ll be able to have fun and see if you’d suit her after a few conversations.
If you do a sport, and it’s a mixed one, then that’s also a good place to start. Just have fun competing against at each other, or working with each other to beat someone else. If there aren’t any girls in the sport you like doing then maybe start a new mixed sport that you know you’d enjoy and will be able to meet new girls.
If worst comes to worst then at least you know that you’d have a chance at making new friends with the other gender. One of the friendships may turn into something more OR they can introduce you to their group of friends 😉.
All in all, just take time out of the x box and the group of friends you have now, and instead start spending a little bit of time with new people.
Good luck 😉