Yes Fancy Feast Cat Food is okay for kittens to eat.
I've fed my kittens Fancy Feast and those kittens grew up to be healthy adult cats and they are still with me today.
Fancy Feast is made for both kittens and adult cats to eat so if Fancy Feast cat food is what you have or what you plan to buy for your kittens it will be great food for the kittens.
Friskies cat food is also good for kittens as well as adult cats.
I also fed my kittens some Friskies cat food and still do now once in awhile.
The cats also eat some dry cat food along with the can cat food of Friskies.
Feeding the kittens or cats too much canned or wet food can cause diarrhea in the cats or kittens but in moderation the wet cat food or canned cat food is good for the cats and especially kittens.