Looking for tips for first ever raid

I just started playing classic for the first time about 6 months ago. I’ve now reached level 80 Disc Priest and looking for a guild to raid with. I don’t have experience with any of the raid mechanics, but have been running H+ dungeons often and I know I can be a decent raider if someone is willing to give me some direction. My gs is 3.9k currently. Wondering if I can start raiding now or if I should wait? If so I think Nax is first? Anyone know of a guild I can raid with that doesn’t mind a raid noob?