Hotel booking schema

There's no one correct way of doing it. What I would do, is to introduce another table on top of what you already have. A table that I would call ReservationHeader, this is the table that would hold a header information and then beneath it I would add another table called RoomReservation which will hold multiple bookings related to ReservationHeader. FInally, I will create another table called Room which holds all data about rooms;

Customer {id (pk), Customer_Name, etc, etc, ....}
ReservationHeader {id (pk), customer_id(fk), reservation_date, etc, etc, ...}
RoomReservation {id (pk), reservation_header_id (fk), room_id (fk), check_in_date, check_out_date, etc }
Room {id (pk), room_number, room_type, etc, etc, ... }

See the diagram below for clarity. You can then add other fields and build on top of that.

You might also might try to think ahead and consider how you are going to query the tables to check for room availability. There are already plenty of good answers covering that stackexchange.