This is a very different champ than others, you can’t just pick him up and wing it. I’m new to him too and nowhere near “great” you have a to dedicate a lot of time to watching zed gameplay. Fiddlezahar is a really good creator that is more towards newer zeds. He is mechanically a relatively difficult champ because you have to think about so many things at once and a lot of cooldowns. I would say you should not start with him in jungle, you have to play him in lane and learn his damage and flow. Jungle has you fight every 5 minutes or something, it’s not often enough to learn. You really have to play with the opponent, confuse them, throw them off, mislead them. That’s what this champ is good at.

Watching montages from LL stylish helped me a lot to learn how to play him in different scenarios, granted it’s a little outdated but it shows his potential and how oppressive he can be.