i really want to be a support main.

thats how support works, you peel for carries to do damage. what they also do slightly changes depending on the support type, but for the most part you exist to help the rest of the team rather then go in solo.

but if you're looking to attempt a carry, play mage ones like brand, zyra, or "lux"

Its not like other roles are better off than support with a bad team. Play what you think is fun not what you think is best, especially since you seem to be inexperienced.

If your team is bad as a support all you can do is peel for your monkies and hope that if you peel long enough they can succeed.

When i start not believing in my team anymore, i tend to play more champs like Nami and Soraka. At that point I can counter engage when someone comes in, i can annoy enemies by constantly surviving, and heal my team mates and hope when they realize they are NOT winning the trade.... that they will back up and let me heal them more.

Otherwise Blitzcrank ive found people MIGHT actually have a clue how to play with a Blitzcrank. So he is another that i pick simply because i do not trust my team to have a clue what they are doing. If they do? Good. They get fed fast. If they dont? Its a 50 50 chance of them not getting fed, or still getting slightly fed.

If you have faith in your Kogmaw/Kaisa/Vayne/Lucian ADC then Braum/Lulu works great with them.

For Draven and most other ADCs (ive just found Dravens to know how to play with her the best) Leona. Nautilus also works well. Janna makes Dravens happy as well if there is other tanks on the team in top and/or jungle.

For jinx she works with most supports.

Alistar works with most ADCs.

I personally dont like Nami with Jhins, due to them never having a clue how to play with one.... but i hear it works well, i prefer Zilean with him though. If you can hit the double bombs they have an easy binding and they might do something more... or they might not. All depends.

Thresh also works well with most ADCs.

If you want to be a support but also have agency, pick a champ from one of these two categories: Pick Mage: Morgana, Zyra, Lux, Brand Engage/Catchers: Pyke, Thresh, Leona, Rakan

Champions like that fit the support role but also have the ability to strongly impact the course of the game on their own.

(Just don't pick Blitz. Don't be that guy. Friends don't let friends play blitzcrank.)

If you really want to carry from the support position play Zyra (52.6% win rate) or Brand (51.4% win rate). Though Sona is #1 atm with a 53.3% win rate.