The Ender Compass makes it so much easier to find strongholds and subsequently End Portals. All you need to do is craft the compass and start on your path!
It will start to direct you as you walk and just adjust your step as you would any other compass in the direction it points. Once it starts wavering back and forth trying to point the right way, you know you’ve found the stronghold. Just dig down until you hit stone bricks!
And then it’s just a matter of fighting and scavenging your way to the End Portal itself.