Report him it is called Extortion and adds another felony charge to rape.
By report him, I mean police not school authorities. I don’t trust school authorities but that another conversation we can have sometime.
If you are underage younger than 18 and he older. Age difference is defined by law. He may be guilty of statutory rape.
The police will collect a statement from you and go from there.
You don’t have to live like this.
Are you in the UK or US?