I am 30 years old now however back when I was 18 I got sent a nude photograph of a non Muslim student. I did the major sin of forwarding it to my friend. I feel so bad about it to this day and I don’t know how to repent. Does haq Al nas apply here? What if reputations were ruined? Does it matter if she was non Muslim? I’m so upset about this until this day

Doing so was a sin.
1- Sincerely regret it and ask Allah to forgive you
2- Do a good deed like paying charity and gift to that person who was exposed, and ask Allah to forgive you for what you did and to help that person for encountering any difficulties that were caused by it