Young kittens by the time you get him, say by 10-12 weeks should be fully weaned. Give your kitten milk for some more time to meet calcium needs till he settles on a balanced good quality diet.
As he grows older his ability to digest lactose decreases so reduce its milky feeds or he may suffer from diarrhoea.
Kittens have small stomachs and they will be able to eat only a little at a time. So daily intake should be split into a number of small but frequent meals. Two or three meals a day at set intervals is a good pattern.
By six months, they should settle on two meals per day morning and evening entirely on solid foods. The amount they need will vary individually with each kitten. Feeding according to demand should be the rule.
A cat can be fed a maintenance or adult diet once it is 10 months to one year of age. An adult cat with normal activity requires only a maintenance diet- enough to maintain a good body condition.
A healthy cats body condition is one in which the animal is well proportioned with an observable waist behind the ribcage, and ribs which are not clearly visible but that can be felt with a slight fat covering over them.
Cats require a higher level of dietary protein in their food-about twice as much as dogs- and at least one-third of their diet should consist of animal protein. A good diet is rich in fat, which the cat's digestive system is equipped to cope with easily.
Commercially prepared cat foods are available from shops as dry food, moist (canned) food and semi- moist food. Dry food is easier to serve and won't spoil if left out for the day. It's also considerably cheaper. Also these foods exercise the cat's teeth and gums.