>>120415684specific rune pages are required for jungling, so if you're pre-level 30 or can't afford the right runes for jungle, it might be best not to attempt the role. if you're simply having trouble learning how to efficiently gank/farm/pressure objectives, watch a couple high-elo jungler's streams (meteos, nb3, theoddone) and emulate their playstyles
in terms of picks, you probably want to try to get good at 3-5 champs. a good selection is elise (high burst, strong cc), rek'sai (good scaling, can go tank or damage) and gragas (very tanky later, strong cc with ult and e). if you're having trouble with high mechanical champs, try more farm-oriented junglers, such as yi, ww and shyvana
don't be afraid to play what you find enjoyable, though. if you want to main fiddle then go for
it.as long as you enjoy playing a champ, and aren't totally mechanically retarded, you can eventually get good with them.