Indoor Cat

Cats are different from dogs, because they can have a happy life at home, especially if the cat never experienced a different lifestyle.

Sleep

Cats sleep most of the time, about 16 hours per day. A comfortable bed can therefore contribute much to the satisfaction of your cat.

Play

If your cat is most of the time indoors, be sure to put at their disposal a range of toys for entertainment and exercise. If you do not do that the cat will be bored and restless and can play with any objects of your house, maybe damaging them.

As an alternative you may consider getting 2 kittens instead of one. Thus they will play with one another.

Nails

Cats need to sharpen their nails. Scratching and sharping nails is an instinctive behavior of cats. To avoid that your cat scratches your doors or even your furniture you should give a post to your pet. It can be a trunk, preferably placed vertically, or you can buy one post in animals' stores, which usually has toys and a platform on top for the cat to climb.
Whenever you see that your cats starts to scratch something that you don't want to be scratched, take the cat and put his/her feet on the post.

Avoiding accidents

The interior of a house is not a completely secure space for a cat. There are several dangers to be avoided. Some open lids could be dangerous. You should make sure you close the lid of your washing machine, or the lid of your garbage can. Some plants can be poisonous. Objects on shelves may be overturned. You should also keep the cat away from cooking pots and uncovered food. Some smaller objects can also be dangerous, such as tacks, nails, spools of thread, glue, elastics, etc.

Grass

The cat needs grass as a source of fibers. The grass can also help cats to free themselves from the balls of hair they accumulate in stomach, by vomiting. Provide a ceramic pot that your cat can reach. It may be grass, thyme, sage, or parsley.