You have to call Disney to find out if there is availability with the Free Dining option at the CSR. Chances are there are, but you need to call Disney to find out if there is and then have it added to your trip.
Also, if you only currently have a room only reservation, you need to add the purchase of a ticket (and it only needs to be a one day ticket) and then the trip will need to be paid in full 45 days out with a $100 cancellation fee after 45 days and $200 closer to the date of your trip (but I can't recall how many days.)