Hi Deborah and welcome to the Mom's Panel!
Once you have logged onto the Walt Disney World website, click on 'Where to Eat' followed by 'Make Dining Reservations' and you will be taken to
THIS page.
At the bottom of the 'Make a Reservation' box, you will see that it says 'I want to use my dining plan to book reservations' If you click on this link you will be asked to confirm your Walt Disney World reservation. Once you have entered your confirmation number, last name and arrival date, you will be able to book your dinner shows without the need to pre-pay.
As you are on a dining package, there must be a guarantee to a valid credit card. If you fail to show and do not cancel your reservation, your card will be charged a penalty.
I hope that this information has been of help and wish you a magical holiday!