@Jean4997 You are very new, so do not accept any booking that you are not very comfortable with. If this guest has booked with Instant Booking , then contact Air BNB and ask that the booking be cancelled. If he has not booked yet and has not answered your questions then decline the request.
After you have more experience you will feel more confident about guests. You may think you have been clear about your requirement that only men in a couple are allowed, but you do not specify that. From your description, you allow couples. It is possible for the couple to be two men.
Why don't you start with women only. You can change it later when you are more comfortable.