Hi Sarahdawn and welcome to RabbitTalk. :welcome:
I split your post off into its own topic because it was off-topic where it was and it is doubtful it would have got many replies there. It's better to start your own thread for a new problem.
There's not much I can suggest for you to do. You don't give us many details, but the doe sounds inexperienced. Many first-timers do not kindle in their box and some lose their litters. I am assuming the kits she is eating were stillborn. It is normal for a doe to eat dead kits in order to clean up and also to avoid attracting predators. It is instinctive behaviour and not something to worry about.
As to why the kits are stillborn, it's difficult to say. You could try giving her a TUMS (calcium antacid) as sometimes a calcium boost is helpful at kindling. Other than that, I can't think of anything you can do to help. Does shes seem distressed?
If she produces any live kits, they should be transferred to the nestbox and given some kind of bedding if she hasn't pulled fur. Teased cotton batting or cotton balls, dryer lint (preferably not heavily scented) or feathers from a pillow all work for this. She may or may not feed them, but they must stay warm for them to be able to digest milk.
Keep us posted and we will try to help.