What is the best sup ever?

All supports are good in some way. Enchanter supports (Janna, Lulu, Soraka, Yuumi etc.) are good at keeping your teammates alive, while Engage supports (Nautilus, Alistar, Leona) usually start teamfights with their engagements. Then there are supports that have hooks (Also Nautilus, then Blitz, Thresh etc.), with them you can catch enemies when they are alone. Other supports like Senna provide healing, damage, crowd control. There can also be offmeta picks on support like Wukong (mainly paired with Senna) and Veigar (mainly paired with an APC).

I don't really think that League of Legends has the one and only "best" support, but it is really easy to climb the Ranked Solo/Duo ladder with enchanter supports.

Probably the best pick for climbing isYuumi. She is really easy to play and is really overpowered. Yuumi's best pairs are Ezreal and Vayne, so whenever your ADC picks either of those (both champions are really popular) you could pick Yuumi.

I read that you think that Lulu is the best support, now it also depends on pairing. Kog'Maw, Aphelios with her are really good.