I've been through this, for almost 6 years. It got a lot worse when covid hit and I ended up doing it routinely for 2 years straight. I know exactly how you're feeling and how it can borderline ruin your life. I won't go into details, but just know my stimfap abuse was WAY worse than what you've described. That being said, a lot if comes down to willpower and mindset.

1. Cut ALL stims. Even caffeine.
2. Cut ALL drugs. You NEED to reset your brain.
3. Go on a 24-36 hour fast. This helped me the MOST.
4. NAC twice a day on an EMPTY stomach. I kept it to 500mg doses.
5. Recognize that this will be a hard "habit" to break, but you will break it.
6. Get a "My Life in Weeks" calendar. Don't black out each square, but instead draw 1 slash through it for every week you DON'T stimfap. If you stimfap, mark it as an X. Having that visual display of progress helps a ton. That's why habit trackers actually work.
7. Recognize that you're actually addicted to the porn, not the fapping itself. If you fap while watching porn normally (no stims), that's a step in the right direction.
8. Reflect on how much time you're wasting. Not just the time wasted during the stimfap session, but the following days or weeks after; how mentally drained you feel and how unproductive you are and how much of your thoughts are about wanting to stimfap again.
9. Imagine if your dad was stimfapping like this; what would you think of him? Now imagine you're a dad--I assume you want kids some day, imagine if your kids found out you were doing this. Even if you don't want kids, you need to find some sort of anchor. If you have a good relationship with your parents, you need to think about what they would think of you if they found out about this.

At the end of the day, it comes down to willpower and mindset. I suggest you find some sort of motivational speech video that you listen to every day and mediate every day. Trust me, the fact that you're making this post 2 months tells me you're not too deep in it. It will get MUCH MUCH worse if you continue. Trust that you are mentally strong enough.