Arthur knows a lot of basic recipes by default though some of the more rare recipes can be obtained by finding Pamphlets or buying them from a Fence. Whenever you skin an animal, you’ll automatically obtain several portions of its meat. A medium-sized animal like a deer or a boar can yield 4 raw meat immediately so you don’t need to slaughter a lot of animals to keep yourself supplied.
While you can plainly cook a meat that restores all cores (depends on the meat quality), you’ll have the option to season it if you have any of the three: oregano, thyme, and mint. Seasoned mints yield gold cores on specific stats while also greatly restoring the other cores. Keep at least one of each for your needs.
After cooking, you can eat the food immediately or stow it. Don’t worry since stowed meats won’t be spoiled so you can keep them in your inventory as long as you want. However, they do take up inventory space, preventing you from harvesting more animal parts so hoarding is not really recommended.
As long as you have the available ingredients for recipes, you should be able to craft useful consumables like tonics, baits, special arrows, special ammo, special throwables, etc. Certain special ammo and arrows can only be crafted from the camp so keeping a good stock of these will help you a lot especially if you're hunting. When crafting multiple items like ammo from cartridges, press and hold X for Arthur to craft them continuously as much as your materials allow. You won't be able to craft additional items if they're quantity is maxed out.