Dear Muslim fellow, you must not eat food from KFC. It is not halal. It actually depends on your country. In the US do not eat at non halal restaurants buy you may eat in the middle east. In the UK McDonalds is halal. For meat to be halal it has to be slaughtered in the name of Allah, and the animal being slaughtered cant get hurt. The process should be painless for the chicken or cow and for that a sharp knife should be used. Kosher meat can be consumed because Jews believe in one perfect God.
If it is not halal you should not eat it obviously.