Iron ingot is a very useful item, it is used to craft iron armor and tools. You can make an iron ingot by melting the iron ore in a furnace or blast furnace.
To make an iron ingot, you first need to bring one piece of iron ore. Go to the underground mining area and break the iron ores with the help of diamond pickaxe. Then pick one piece of ore and take it in your inventory.
After taking the iron ore, make your way towards the furnace. Use one piece of iron ore on the furnace and this will make an iron ingot for you.