Cats are what are known as obligate carnivores. An obligate carnivore is one that must east meat. You cannot just turn her out to graze in a pasture. The digestive tract of cats has been shortened and optimized proteins from meat. They simply don't have the dental or digestive apparatus to process plant materials. It's therefore surprising, given their physical inability to process plants, that you will still find cats nibbling on plants from time to time. There are many theories for why cats would nibble plants. They may be trying to balance an upset digestion or add missing vitamins and minerals. Perhaps they simply like the taste. Maybe it's a combination of factors. The jury is still out on this matter.
Fortunately, these days, we don't have to go out and hunt for food to feed our cats. There are a large number of very good, nutritionally balanced foods available in pet stores to satisfy any cats' tastes. Try to feed good quality food. It really does make a difference in the health and appearance of your pet. Pick one that your cat likes and stick with it. Cats don't actually need a lot of variety. Changing their food constantly tends to just make them picky eaters.
Nutritional requirements for your pet will vary by age and size. What she needs as a kitten will be very different than what she will need as an adult. Be sure to follow the instructions on the bag to avoid feeding too much or too little. The average adult cat will need about one cup of food a day. Cats appreciate consistency in their feeding schedules. Try to feed them at the same time each day. Also, try to keep their bowls out of high traffic areas. It's hard to eat your dinner when people are stepping on you!
Try not to feed your cat people food. Some things, such as chocolate and raw liver, are actually toxic to cats. Others cause digestive upset. Remove the bones from any cooked meat you might want to give to your cat. Poultry and pork bones in particular are given to splintering and can injure your cat.
When you need to switch from one type of food to the other, do so in a gradual process. Shifting gradually from one to the other over the course of a week will help prevent digestive upsets. You may need to switch foods because your store may stop carrying the brand you like or perhaps your kitten has grown old enough to graduate to adult food. Do the changeover slowly and your cat will thank you for it.
Feeding treats is something for you to decide if you want to do it. Some people are dead set against them. Others lavish treats on their pets at every opportunity. There are many good cat treats on the market today. Read their directions carefully. You don't want to overindulge your cat and turn her into a furry beach ball with legs. The only other thing that a cat requires is water. Do your best to keep a nice fresh supply of water available for your pet. With a little thought and planning you can keep your pet healthy and happy for a long time to come.