Missable achievement.
In the opening part of the game, after the tutorial, you will go through a shipwreck and find a lit fire. Take a piece of driftwood from the ground and hold it in the fire to set it to flame. Then go forward past the campfire toward the tent. In front of the tent is another, unlit firepit. Put the lit driftwood in the firepit to light the second fire and get the achievement.
I haven't tested it, but you might be able to light it with the flare gun or a candle as well.