Sorry still a little confused lol do we just need reservations for the fancier places or will every restaurant be full if we have to we will break up into groups to eat
Depending on where / when, walkups to Table Service locations can be almost impossible at times. If you want to sit and eat @ a restaurant, with such a big group, you have to make reservations in advance. Even with breaking up your group, you might find a place that could seat (as an example) 2 groups of 4 as a walk-up, but have no room for the rest of your party.
Not all Table Services are "fancy" - the fanciest restaurants @ Disney are called "signature". But any place that has waiter/waitress service is considered a Table Service and takes reservations 6 months in advance (there are a few exceptions to this but very few).
If you do not, you will either have to eat at counter service (fast food type) or else you may find you can get a reservation somewhere last minute by calling - but it might be a place you don't really want to eat, or else in might be somewhere that you will have to spend time getting to - a resort, a different park, Downtown Disney, etc.
That is not to say there is NO chance that you can walk up to a restaurant and be seated, even with your large group, but there is no way to predict that, and I believe it is very unlikely.