i want to play ranked but having problems of who should be my main go to and backups for lanes. for top lane i mostly play darius, garen, currently learning mantheon. for mid lane i mostly play velk, and xer. and bot adc i either play graves, cait, ashe, or kog. i don't have a jung champ cause i'm trash at jungling and havn't found a supp that i like playing yet. any thoughts?
well you should learn at least 1 champ for jungle and support, because you will have to fill sometimes.
Easiest jungler in the game is 
he recently got nerfed but he's still viable, not OP anymore, but definitely still viable - and couldn't be simpler to play. He's got enough natural sustain that he won't have any trouble farming jungle creeps, and he's got a point and click gank after 6
You can still gank pre-6 if they're overextended and you're in the area.
If you want someone with better ganks try 
jungle
As for support you can play 
, just build 
and then build whatever.
If you need a sustain support 
is amazing and also extremely easy to play
