I like a girl and i don't know how she fall inlove to me ?
Actually, it depends on what kind of girl you like.
If you don't know that, ok, there are other ways.
The first way is to perfect yourself every day. Maybe exercise more regularly, read a few more books... Reading helps you gain a deeper knowledge. Girls will be attracted to you if you can answer any their questions.
After that, make time for that girl. Find out more about her hobbies and friends...of course herself.
Finally, after gaining knowledge and knowing what she likes, you should be more concerned, always say things that make her happy, invite her to eat, hang out ...
In fact, the longer you guys take time together, the easier it will be to create affection. When there are disagreements, how will you handle them to make you happy?
My advice is to calm down, let she talk, listen to her story. If you disagree with her idea, let her know.
Hope this helps you.