To start using a map in Minecraft PC, you'll need to craft one first. This is done by combining eight paper pieces and one compass in your crafting table. Once you've got your map, you can start exploring and mapping out your surroundings.
As you move around, your map will automatically update to show you the terrain, structures, and biomes you've discovered. You can also use your map to mark important locations, like your home base or a hidden cave filled with precious ores.