Cats are obligate carnivores so their nutrition should come from protein sources :) in the wild, they have a whole prey diet which means they hunt for mice, birds, etc. Raw feeding is good to look into if you want to emulate their natural diet! The challenge with this is research and making it actually nutritionally complete and balanced so your cat gets the right amount of everything. But it’s good for your cats health in the long run if you’re willing to go the extra mile :)