League of Legends (LoL) Question: What champion should i buy for Jungle?

Are you already maining jungle? or do you want to now? if you already are
what champs have you played already. if you are starting now check out these posts :> Jungling and jungle champ

They have some good pointers on starting and a guide onto which champs you should look into.

try warwick, graves, jax, leesin, shaco and twitch these are very easy to learn and they deal a lot of damage can even cary the team. And it also depends on your playstyle. And what so good about exploring each one of these that they are very easy to learn and very fun.

Warwick is cheap and easy to learn on as well as can be a powerhouse. I really enjoy playing as kayn although he's pricy. Chogath last i checked has been absolutely amazing as jungle (played him for a bit). rammus and vi always seem to ruin my life so thats a good option. finally, master yi is always a good cheap one to learn

warwick, rammus, khazix, master yi, shyvana, and xin zhao are all really good right now. it all depends on your playstyle. warwick has sustain and is good in 1v1s (so is shyvana), rammus is a tanking meatblock, and khazix/master yi/xin zhao are sneaky damage bois.
khazix, master yi, and xin zhao are more risky out of this list

Shyvana, vi and warwick are really great, both tanky and have great damage potential. Very difficult to stop them once they are fed and also have a very strong game as soon as they hit level 6.

You always have Master Yi to take since he is easy to learn, strong and cheap. You also have Lee Sin, who is rather strong if known how to play.

S8 Shyvana is really good because of Press the Attack and buffs

Rammus. Warwick. Udyr. Cheap, strong, and easy to learn the basics.

its about your elo if you are low elo you should main lee sin or yi
if you are hugh you should try to play all champions in jg