Homosexuals of reddit, can you please help me with this situation?

Ok, so I am watching my 11 year old brother for the week while his mom is recovering from cancer surgery. He is also having a hard time since our dad and his mom split up 6 months ago. He is in a really fragile state.He got a little angsty with me so i sent him to his room here at my house without his tablet. I realized i may have been a bit too harsh so i suggested my husband download a gameboy pokemon emulator. Thats when we found the porn on his tsblet. Lots and lots of gay porn. I am totally cool with him being gay, i will be his biggest supporter but i am worried about how to go about the situation.His parents are homophobic and will try to beat the gay out of him. Obviously I am not going to tell our dad or his mom. I want to let him know that it is okay to be gay, and want to show him how to browse thr internet safely so he doesnt get caught before he is ready to come out to the family.I have never done anything like this and ANY advice would be helpful.Thanks reddit.