Mine logs from any tree (Oak, Spruce, Birch, Jungle, Acacia, Dark Oak, Mangrove)
Convert logs to charcoal in a furnace:
Place logs in the top input slot of a furnace
Place fuel (any burnable item like wood planks, sticks, or coal) in the bottom fuel slot
Wait for the furnace to smelt logs into charcoal
Alternative (faster in Java Edition): smelt wood using a blast furnace to get charcoal (if available for your version)
Alternative (most direct): craft or use charcoal blocks by smelting logs and then placing charcoal in a crafting grid to make blocks
Use charcoal as fuel or ingredient (e.g., torches, crafting items that require charcoal)