What do I do?

So she is 2 years older (17). We are in the same grade and when we see us in school we have strong eye contact and we always smile. The problem is that she has many friends that are her age and are the „cool“ guys. I dont want that they all make fun of me and stuff like that. Another problem is the age difference. I mean in one year the is 18 and with that in my country she is an adult. What do you guys think should i do?