need tips on how to end when i carry

alright so im not level 30 yet but this is my smurf im low to mid gold on my main basically i play blind and take it serious since i want to quick level but unfortunately theres so much throwing going on im 10 and 4 yi at 15 mins and im doin good but my bot lane is struggling so i go to help them get 2 kills and chill but they feed then 6 kills but im like whatever i can do this thennnn team fights come around and i go up to team fight and its a 3v5 cuz me and my top illaoi and lux are the only ones fighting while botlane has 0 awareness and is chilling in the jg sorta close to us coming into the fight almost after it ends and this happens every game just about and its starting to put me off playing league so i want tips on how to end or how to carry hard enough withouth 2 players