Young... My advice is don't go for a girl until a bit later. 13 year old girls and 12's are drama queens. I get your feelings but listen to my experience here, be careful who you trust with your heart at any teenage age. Girls at that she are very manipulative... But if you want advice to get her, just treat her right. Don't try overly hard, don't pick a fight with her boyfriend. Actually better yet, be nice to the guy, unless you need to defend her. Show her you're a decent guy. Don't be the guy that tries to show up her boyfriend as a puss. Be the guy a girl wants.
A 12 year old isn't supposed to have a bf/gf you are all giving op wrong advises he should study instead of looking for a gf