What is the process of Muslim marriage?

I want to ask you something about Muslim marriage. I am 22 years old and want to marry a girl who is 17 years old. According to Muslim marriage law, a girl is considered of marriageable age if she has reached puberty. Her parents are not ready for our marriage, but my parents are supportive, and she wants to get married because she does not want to stay with her parents. She asked me to find out if there is any law that allows us to get married in court under these circumstances, or if we have to wait for one more year. Kindly please help, sir.