Hi agree with the others here suggesting having a conversation about it. And when you do, try to come across as curious and neutral. If you come across as judgmental and angry he might get defensive right away. It’s okay to share your feelings and say it hurt you and you’re upset OF COURSE, but how you talk about it is important. This is how you build trust too with your partner. No one wants to be judged for something they do.
I found out my fiance uses porn from time to time and it baffled me for a minute, but then I took a deep breath and just asked questions. Instead of feeling like I wasn’t enough, or he was “cheating” on me in a sense, I wanted to understand why.
He told me that if he doesn’t masturbate often enough it gets painful and uncomfortable. Porn is just a vehicle to help him succeed in that so he can move on to the next thing. It’s hard to do it without porn. Now, he’s not buying only fans content and saving things to his computer… but to each their own, I guess… anyway, take this with a grain of salt as I don’t know your situation or you 😍 but the moral of my story is being curious helped me understand and only strengthened our relationship further