You have learned a hard lesson in the consequences of lying. Trust and truth are the basis for any lasting relationship. Once broken, trust takes a long time to reestablish. I’m not at all optimistic that you can keep this relationship. Neither are you.
You are probably correct that your boyfriend will think of you differently once you do tell him the truth. I think you’ve known that from the beginning. Maybe you thought you could continue the lie. Maybe you thought that once he knew and loved you, he would change his mind about his values. But values are very, very difficult to change. From his point of view, if you now tell him the truth, he will think to himself: “You lied about your virginity. You lied about only being sexual with your ex. Now you are telling me you’ve had multiple partners??” He will wonder when the lying stops.
Fortunately, you’ve only been with this guy 2 months. There will be nothing gained by lying some more. All you can do to perhaps salvage this relationship is to tell the truth and see what happens. If your boyfriend can’t accept you as you are, then you owe it to both of you to end it.
I wish you well.