how to jungle? (+help on targeting)

skip the formalities because i dont know how to start a paragraph. how do you properly jungle? everytime i play a jg champ that isnt master yi i feel like im always behind and always performing worse. i cant take objectives and everything falls apart. also it feels like i do no damage sometimes (with riven and jax)

another thing i frequently mald about is the targeting system. i just came back from the game after quitting during glorious jinx season so idk if targeting is fixed but whenever i try to take obj, it feels really hard to steal/secure because sometimes smite wont even prioritize the obj

now you can take that last statement with a bit of salt because im too afraid to even test if im wrong or not (im always dragging the smite instead of pressing just to make sure)

sorry for long post and i hope i made my point clear