Cats unlike dogs, can live indoors quite contentedly, especially if they have never known any other life. If you intend to keep your cat indoors, make sure it has plenty of toys for amusement and exercise. Better still get two kittens at the same time, so that they can be playmates and be company for each other. If you cannot get two kittens from the same family - try and get two kittens from different families on the same day - then when you get home and introduce them to each other - they will both think that the other has lived at your home before! Generally, kittens from different families will hit it off very quickly - elderly cats have a much harder time hitting it off with another cat that is a stranger to them. Feeding time is a good time to introduce two cats to each other - make sure that each cat has its own dish and keep them well apart.
Indoor cats can sleep for 16 hours or more a day, so a comfortable bed is very important for them.
An important item for an indoor cat is Grass. It is an excellent source of fibre for your cat. It also acts as a useful emetic, which will help your cat to regurgitate hairballs. Other alternatives (fresh not dried) for Grass are Catmint, Thyme, Sage, Parsley, Chickweed, Lawn Grass, Colt's Foot Grass, Cereal Grass such as Wheat or Oats.