Wanting to improve

Hi i've been playing LoL since season 4 and i never really took the game serious just playing casually with my friends. but this season ive tried to climb in ranked ive watched many videos in "how to improve" and they've taught me some really useful tips but non of them have mentioned how to deal with a bad team and how to climb when at least one lane feeds i play top and i can only help when my tp is up. i try and carry but most of the time i cant. i really do think I've improved some here are some things i've improved on

.not feeding as much .Trying to CS better .Harassing/trading better .Not flaming/Shit talking Trying to look at the mini map more often .Trying to tell my team dont just fight to fight. fight over an objective .Trying to get early towers/objectives .Playing mostly 2 champs .Trying to keep my spirit up (hardest thing to do) .Trying to put more wards down more often .Trying to shut down my laner ASAP

I've improved in those fields some more than other but all improvement is good

I've started maining swain in the top lane but sometimes i get mid no big deal

i just dont know how i can get better when every time my team is just feeding if mid doesnt feed bot does and their whole team just snowballs off that lane and it spreads like a plague to my lane and then to top but if i feed its my fault i know and im not saying i dont feed im just saying i do it alot less

Any tips on how to improve,climb,and keep a positive attitude would be greatly attitude

BTW im bronze 5-3 it bounces from those often and i main swain top