What can l do to make this girl mine?

there is this other girl l really love and l even told her so, but she told me that her heart belongs somewhere and it was her first time having a boyfriend so she said she wanted to settle down things a bit... She can't stop smiling at me whn we are talking and when l keep trying she tells me that l deserve someone better than her.. L don't know what to do next pliz help me l can't just let it go.. I really love this girl.