Stockpile supplies. This is a pretty crucial step, and there are several very specific supplies you will need to locate the stronghold, and to access the end game. Mine ores. You will need to find at least 5 diamonds, 64 iron, and several stacks of coal. You will need seven diamonds if you want a sword, pickaxe and an enchantment table, and even more if you want armor. Craft tools and armor. You will need at least 1 diamond sword, 1 diamond pick, 1 full set of iron armor, a bow, arrows, and several stacks of torches. Build and light a Nether Portal. To create a Nether Portal, you'll need at least ten obsidian blocks. Make a hollow standing rectangle, with an opening 3 blocks high and 2 blocks long (corners are not necessary; you can use any block as a stand-in). Then strike the inside of the rectangle with flint and steel. The empty inner space should turn purple and start to make interesting sounds. Enter the Nether. Stand in the portal and wait 4 seconds to be transported into the Nether. Make sure you have your flint and steel for relighting the portal in case it breaks from a ghast and plenty of food to keep yourself well-fed. Find a Nether Fortress. A Nether Fortress is a structure in the Nether that contains Nether Wart and a Blaze spawner. They can be somewhat hard to find, so it could take a while. Craft Eyes of Ender. These are crucial in helping you locate and unlock the endgame. You can craft an Eye of Ender by combining blaze powder and an ender pearl in the crafting grid.
This is a shapeless recipe, and the ingredients can be placed anywhere in the crafting grid.
Blaze powder is crafted by dropping a blaze rod anywhere in the crafting grid
Throw an Eye of Ender. It will fly up and move in the direction of the nearest stronghold, a very rare underground structure. You throw an Eye of Ender by right-clicking while holding the Eye
Repeat the previous step until a stronghold is located. You will know you have found a stronghold when the Eye of Ender starts flying towards the ground.
The Eyes have a 1 in 5 chance of being destroyed after each use so bring a lot of them
Excavate the stronghold. You will probably have to dig a bit to find the stronghold.
Secure the area. The stronghold will be full of mobs, so clear it out and light it up.
As usual, don't dig straight down, as the End Portal frame