You can't. You have to find a stronghold with a silverfish spawner and when you find one you have to place the end portal blocks with ender eyes and then it will work.
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In pure survival, it is impossible to make an End Portal Frame. If you encounter a naturally generated portal, you must place eyes of ender in each of the frames. An eye of ender is crafted by an ender pearl and blaze powder.
1. You can't make one from scratch 2. You can find one in a stronghold. You need to put ender eyes in the outside of the portal slots.
First, you have to obtain 12 or more Ender Pearls that you get from Endermen. Then, in the crafting table, you mix them with Blaze Powder, which you get from Blazes in the Nether. Then, you should get Eyes of Ender. You locate a stronghold by throwing the Eyes of Ender into the air. When the Eyes of Ender start floating toward the ground, you dig until you come to the End Portal. You place the Eyes of Ender in the portal, then jump into the portal. Good luck killing the EnderDragon!
You can't make a portal to the End outside of creative mode. Instead, you must find it in a stronghold using eyes of ender.
You can create an Ender Portal using Ender Portal Frame blocks from your inventory and activate it using Eyes of Ender