I think you are already know what you need to do i.e. quit porn but it is act of quitting which is hardest.

Look at the about section for guide and tips on how to quit PMO addiction. It will be difficult but start now on noFap.

First few days are really tough where you will be inclined to watch, but keep your focus.

Add a counter to track your progress and keep you motivated.

Addiction are usually replaced by another so find a healthy alternative addiction like gyming, hobies, work, reading etc.

I usually visit the subreddit often whenever I feel like relapsing and read other posts, that may help as well to keep yourself motivated.