a little while into the game you will be introduced to the concept of crafting items away from the campsite. you hold
to make bandages using 1 Herbs (leaves), and 1 Cloth. if you are at full health you cannot do it, so just make sure to do it at least 3 times after receiving damage during the game. i believe the first time the game requires you to do it as a tutorial, so there's one down already.