Why Is She Like This?

Hello, I want to ask you for an opinion about what you think about it. I've only liked a girl for about two years at school, I've only talked to her twice. She's following me on Instagram, but I haven't liked a single photo before. Every time we see each other life, he pretends he can't see me, but a lot of times our eyes have caught on. When I asked her for a lighter on purpose, she gives it to me and doesn't even look me in the eye. I have all her friends in her class except her. What can I do in such a situation, because I just like the girl very much? I want to get to know her life, but she's acting very cocky.