Thank you both for responding 
I can imaginen that my view on what healthy sexuality could be indeed distorted after all those years. I hope I can fix that with some professional help.
I have read/watched some things on the subject. But now that you’re the third person recommending me the book, so I will read it for sure.
I already tried to quite a few times, which lasted a like around 2 weeks at most. But hopefully with all the friendly help and support I get here, it should be somewhat more durable.
Should I tackle on thing at the time or try to quit both mastrubation and porn in one go?