Persian cats need a good diet to stay healthy.A fixed formula cat food is the best, which means the same amount of food is given to them every time. But corn should be avoided since persians can't easily digest it.
Persian cats only eat what they like. One cat might like to eat something which the other might not. Just like humans differ from each other in their likes/dislikes, so do persian cats.
Some cats like eating chicken and fish, while others only enjoy eating cat food.
But avoid giving your cat the biscuit food that is available in every supermarket. This can be very dangerous for your cat's life in the long run, especially if you're living in a hot country like Pakistan which has a very unpredictable weather.
Milk should be avoided since it causes diarrhea. Milk should only be given if mixed with water.