Season 1 : Phantom Blood and Battle Tendency
Season 2: Stardust Crusaders/Stardust Crusaders: Battle in Egypt
Season 3: Diamond is Unbreakable
Season 4: Vento Aureo
Start with Phantom Blood; part 1, Phantom Blood, and 2, Battle Tendency, are both covered in the first season. Jonathan's story is literally 10 episodes, it makes no sense to miss it. You need to start from the beginning because Dio and Jonathan are relevant with everything else that happens after, everything stems from their conflict,
especially for part 3 Stardust Crusaders
And Dio is very significant for part 5, Vento Aureo, and even more for part 6, Stone Ocean.
The anime is currently up to part 5, Vento Aureo, and it's still on going. I haven't started watching it yet because I don't care that much about Giorno's story, it's the weakest Jojo part but keep in mind that still makes it better than 98% of the anime out there. So, I say start from the beginning and go from there, and if you like it give the manga as shot. And trust me, if you want read it find the colored edits because if you read it in black and white it's going to be impossible to understand especially from part 5 onwards.