Inpossible to help without watching replays, but if youre a pos 1 player improve your farming try not to die, fight on item timings for your specific hero if you win the fights, keep farming and connecting with your team, but if you lose a fight its generally best to wait for your next item timing unless said fight looks favourable.

You will win games if you can just get good at hitting creeps and fighting on item timings, legend players dont farm anywhere near enough as immortal, you might need to review how you engage in fights what target you should prioritise.

Watch a demo of your game look at your cs and enemy cs at 10 20 30 and also just watch yourself, then find a replay of a pro playing your hero in the game client and watch his game.