Hi Sparklebunny, welcome to RU!
Some basics about buns:
They need A LOT of space, particularly if they're youngsters. Forget the idea of an indoor cage - instead look at bunny proofing a room for them to live in, then let them free range around the house when you're home.
They can live for a good long time. I just lost my boy at nearly 11, so be prepared for the future! Consider insurance or putting away the equivalent money each month in an 'emergency bunny fund'.
Ideally rabbits should be kept in pairs or trios. Boy/girl pairs usually work best, but I had brothers who could not have been closer. Spaying/neutering is essential. If you adopt your buns from a decent rescue they'll have had their ops already, which takes a load of the stress off you!
Hay is the single most important aspect of their diet (and grass of course). If you can buy it by the bale from a farmer it'll work out most cost effective, and its much yummier that way. Pellets aren't really necessary at all but if you choose to go this route they won't need so much fresh food. If you scatter feed the pellets that's great enrichment as it's a more natural way of eating and gets them hopping about. With veg, it's dark leafy greens such as spinach, broccoli, watercress and rocket that are best - carrot should be limited as it's so high in sugar.
Vaccinations are necessary even for house rabbits!! The 'combined' vaccine covers them for myxi and VHD.
Enrichment and toys are very important, but needn't cost the earth, although they easily can if you want them to - check out The Hay Experts'...! A large cardboard box to hide in, a loo roll stuffed with hay and dried treats, an apple tree branch, a small ball to roll, a plastic or wooden ring to pick up and throw, a tunnel made from old boxes or a blanket draped over a chair... that sort of thing. A digging box of soil or sand always goes down well, though chances are they'll also pee in it.
If you want them to go outside at all, make sure the whole garden is completely bunny proof (no escape routes/poisonous plants etc) but you still want to supervise them at all times. Cats, foxes and crows are terrible predators, so your buns will never really be safe out there alone. In the house you need to think about wires, soft furnishings, house plants, books on low shelves, precious wooden furnishings and of course, other household pets!
Where were you thinking of getting your buns from? Please, please don't go to a pet shop. Did you know the rabbits in Pets at Home are bred in Spain, and taken from their mums too early so they're still at that 'cute' stage when they're imported into England? Not something you want to support! A pair from a rescue wold be ideal as you're most likely to get an honest back story (at least from the time they've been in the centre), they'll be neutered and vaccinated, and you can spend a decent amount of time choosing the right buns for you. If you rehome privately you may find you've been misled about possible health issues, etc. If you do chose to buy from a breeder, consider their setup, how their own rabbits are kept etc. Most breeders use horrifically small 'breeders blocks' for churning out baby bunnies without thought to health and welbeing.
Good luck, and be sure to post piccies of your new family members when they arrive!