Discussion about jungling to help a noob.

I have always been a support main and played a good amount of mid, but I just hit silver and really want to start jungling. So really I'm just asking for help. I want to learn a couple jungle champs that won't be permabanned but are still strong, suggestions there would be great. Also, I've tried to jungle in bots a couple times and usually die to the chickens and have a tough time in general with jungle clear path. What path do you use? Also, I've heard you're not supposed to Gank losing lanes because you're supposed to make winning lanes win harder, but won't I get flamed for ignoring losing lanes? What's the thoughts behind successful ganks?

Thank you for any help!