Hey your father being a terrible father, husband and human being has nothing to do with his sexuality
Cheating is unforgivable
Don't think about offing yourself over something like this he is not worth it
Print and save as many proof you can to show your mom and plan to solve this situation in a safe way your mother might want to divorce idk where you are in the world but I now that such things are really hard and dangerous
Also make sure if your mother is or not unaware of this situation as far as we know they could be beards for each other
i am genuinely sorry and hope everything is okay with despite the situation. and i also hope that you can heal from this, because it can be traumatising. i also would feel bad if i saw my dad doing that - not because of his sexuality but because of me and my mom, and the fact that he’s talking to younger people.
you can always talk to us and despite this being a bad thing that you are experiencing and we (i suppose) never went through that, we will do our best to try and help you

Before I start with what I want to say, I’m really supportive of the LGBTQIA+ community, in fact I’m even Asexual myself, but with this happening to me I feel so upset to the point I just want to off myself. I have access to my dad’s fb account, and I saw him adding all these men with half naked pfps and I even saw him chatting with a person and asking for dick pics, and I even saw him chatting with a guy YOUNGER than me. And it seems like they’re meeting up for I don’t even know what, because I just read that he(my dad) shouldn’t go to where he is, because there were “people around”. I don’t know if I’m overreacting or what, but I feel like my heart is about to burst. Keep in mind that my dad is married to a woman with 3 daughters.