Minecraft resource gathering/Charcoal
You get Charcoal from smelting Logs in a Furnace. You can use any source of fuel as fuel, including but not limited to planks (sensible choice if you don’t have coal but have access to lots of wood), coal or charcoal, or even lava or blaze rods. (sensible choice if you have decided to build your base in the nether since you have access to very large lava oceans and since the 1.16 nether update there are trees in the nether).
Charcoal is in many case, a valid alternative to Coal. It can be used as fuel. One charcoal smelts 8 items. However, you can’t craft charcoal blocks like you can coal blocks.
Also, it’s used in the crafting recipes of the campfire, the fire charge, the soul torch, and the torch, though in all of them, you can use regular coal instead.