According to all Indian personal and other laws, marriage can only take place between two people with the mutual consent of both the parties, and nobody can compel or force you to marry them.
It looks like you are a victim of criminal intimidation as given under Section 503 of the Indian Penal Code according to which threatening to cause injury to person reputation or property in order to compel a person to do something that he is not legally bound to do, is a criminal offence which is punishable under section 506 of the Indian Penal Code with imprisonment upto two years or with fine or with
You should accordingly file a complaint in a police station describing everything from the fact that he is threatening and forcing you to marry him otherwise he will tell your parents about your relationship and the police will then do the investigation and the court will conduct a trial fro criminal intimidation and award punishment to the boy in accordance with the Indian Penal
Make sure that you save any evidence that you have that can show that he is forcing you to marry him and threatening to harm you if you don’t do the same.
Reference: Section 503 – Indian Penal Code – Whoever threatens another with any injury to his person, reputation or property, or to the person or reputation of any one in whom that person is interested, with intent to cause alarm to that person, or to cause that person to do any act which he is not legally bound to do, or to omit to do any act which that person is legally entitled to do, as the means of avoiding the execution of such threat, commits criminal intim_idation.
Section 506 – Indian Penal Code – Whoever commits, the offence of criminal intimidation shall be punished with imprison_ment of either description for a term which may extend to two years, or with fine, or with both – 202100457-20210007-1308