I need help i got anwsers for my last 2 questions i asked so here is a nother question i need to ask!?

ok so i talked a little bit to the girl i liked i still really dont know what to do im really shy and have a huge fear of getting rejected what should i do i talked to my friend about her but all he said was that she may like you im not going to tell. i saw here with this guy and that was her bf but when i talk to her she smile when i talk to her, she looks me directly in the eyes when i talk to her but what should i do i cant stop thinking about her i need help