Just eat healthy and don’t get fat. I say this because relatively lean (skinny) girls tend to need 10-15lbs total muscle to have a head-turning physique. This can be attained fairly easily when you don’t add in the extra work of cutting as well. When I say “eat healthy”, this does NOT mean starving yourself or going on crash diets, or really anything you will find in a magazine. You know what eating healthy means… stay away from fast food and late-night snacks. If it was made at home (and isn’t smothered in cheeses/butter), you can reasonably assume it is healthy.
Due to some ridiculous societal norms and social media’s absurd “normal” look, I feel it is important to note… At your height and weight, you’re probably already relatively lean or skinny. Most of us here have body dysmorphia, considering this is a fitness forum; don’t get it in your head that you’re fat, because you probably aren’t. The old saying “if it jiggles, it’s fat” really isn’t true, particularly for women (or young women, in your case).
As for training, you could do quite well with any bodyweight exercises and cardio really. If you are able to do bodyweight squats, pullups, pushups, lunges, and most other staple bodyweight exercises with good form, I think it is fair to say you are ready for the weight room… If this is not the case, then I would work on ALL of these before touching weights (I’ve applied this rule to my daughter as well).
As @RT_Nomad said, having a sport that requires you to be competitive will help significantly with this. Soccer and gymnastics are probably a great place to start (my 5y/o daughter is in gymnastics and literally has some muscle from that alone… she’s never touched a weight, only does bodyweight stuff), potentially volleyball as well. If none of this sounds appealing to you, I would focus on your primary compound movements. To stay in good cardio shape, I would consider crossfit style workouts as well (WOD, Workout Of the Day) would suffice to gain muscle and stave off extra fat. Or for a format that is more self-led:
I cannot stress enough the importance of eating healthy. If you are hungry: eat. If you aren’t: don’t. And make sure the food you are eating is wholesome. You are at a great age to have a good relationship with food… don’t starve yourself ever, and don’t gorge yourself either.
Your body is still growing and maturing; please don’t go on a cut or bulk - just eat as I assume you have been, and aim for healthy foods when given the option. Don’t aim to be the Instagram model… she’s not real and doesn’t really look like that - don’t assume you will look like that either. Cutting or bulking at your age is more likely to interfere with hormones you very much need.