Porn is extremely addictive, whether it's real life porn videos, games, doujins etc it's all the same, at the end of the day the all serve the same purpose and procure the same feeling. And the more one consumes it, the more he feels the need for it even more.. just like a drug.
And just like any drug, it can cause some serious damages on the penis (erectile dysfunction/impotence, premature ejaculation) but also on the psychological aspect of sex overall, you'll find people who'll find it more pleasurable for them to actually watch porn/porn games than to perform sex with their partner, or those who start having misconceptions about how to actually have sex, or how a woman's body should look or how their own penis should look etc, due to all the massive porn content they consumed, their vision of how sex "should be" changes and they forget that one is pure fiction and the other is real life.
Personnally, i was addicted to porn and doujins for a few years and i mean ADDICTED, like i needed to masturbate at least once a day, and that kept going for like 4 months or so, then i started noticing that i would ejaculate a bit earlier prior to when i wasn't that hooked on porn.. that's when the alarm rang inside my head, i was a healthy young man in my twenties, in a good shape, athletic, i should not have issue with ejaculation or erection. So i stopped porn, all kind of it, stopped myself from even watching a girl twerk, cause one thing leads to another we all know it oh too well. Months later i started noticing that mentally i felt better, physically i was doing great and i was waking up every single morning with a raging hard boner that would last for several minutes, wich only means that my stuff was in a good shape lol.
Years later, i now can control myself with no issue at all, can keep it hard and going for a good moment, only watch porn or play games once in a while, and the feeling to know that you can control yourself and not be seduced by all that stuff anymore is simply satisfying.
I know there's a lot of teenagers and guys in their early 20's in here, my advice for you would be to try and control yourself as much and as long as you can do, specially if you feel the "need" to masturbate very often, your body and dick will thank you later believe me haha.