This guide will let you know how to make Iron Nails in Icarus. You have to follow the simple steps in this guide to make iron nails.
The first thing you have to do is make iron ingots using iron ore from caves. After that, you have to make an Anvil bench from a crafting bench using 40 iron ingots and some wood and stones.
Then you have to go to the anvil bench, add iron to it, and see iron nails there. You have to make it by pressing the Craft button, as shown in the image below.