why am I so bad even though i feel like I am not

I lose so many rankeds, today i lost all I played. I do what i can, if i play top, bot feeds, if i play adc, top feeds. I decided to play mid but still, I cant roam 24/7 and they feed. My last game for example, 0 2 0 within first 8 minutes and then afk. The game before, i got autofilled adc (i am not an adc player, i bought 2 in case of autofill), both banned . I had to play and we dominated botlane but we also had a toplane who played against a , he fed him so much and lost the first tower so fast, that rengar waqs able to easily dominate midlane and jungle. My second game today, our junge had no clue how league of legends works, he dived at level 2 and dies, not once, twice! then he decides to stop ganking at all, he still died tho because he apparently had his minimap disabled. On the other team a main who ganked non stop (still mannaged to get more farm than ww however that works). It is easy to dodge her Q but i had to 2 times to survive her idk, 5 ganks during the laning phase, later the flash + stun + vi Q and even I started feeding.

My last game, with the afk made me write this post, it also demoted me to silver 4. I dont want to blame it all on my teammates, obviously good players are always able to get new accounts in high elo, i am not a flamer either, not that u think i make my teammates troll. can someone above plat, somehow, help me? I chose tf to get a lot of map pressure and good push but i cant ult to another lane when my mana is low or when the opponent wont stop pushing or when my r is on cooldown as always. my waterwalking is a nice help but i just cant carry for a reason I dont understand.

so please, someone over plat, take a look at my match history, maybe spectate a game ... tell me what I do wrong so i can not only start being a good player and climb the ladder rank but also give my new knowledge to other people in my situation such a friends or forum members!

thanks