Bronze is a shitty environment that is true. There are toxic players at all elos but bronze definitely the worst. The good news is most players in bronze are not that good so if you focus on your game and staying calm you should be able to carry enough games to rank up. It may seem tough or not worth it at first, but i gets better once you get on a winning streak. Bronze is all about learning what to expect from the players around you and carrying games based off that.
Like if I had a smurf account in bronze right now and really wanted to rank up I would play champions I feel I could hard carry with and just spam that each game. Even though I am now a jungle main, I would probably avoid jungling unless I was going to play an assassin. I personally would play
mid is she is easy and I know I could beat most enemy laners and get super fed and delete 3-4 enemy players in team fights later in the game.
Or in the past I would play adc. Bronze adc is a shitty role just because supports and teammates cannot be trusted to peel. But at the same time I am good enough to generally beat the enemy bot lane and get a lot of free kills, which I can usually use to hard carry the game regardless if I have peel from teammates.
Just have to figure out what your comfortable with playing and go from there. Just ignore your shit teammates and focus on stomping the weak players on the enemy team. Focus on covering lanes that has no teammates in them since after 20 minutes most bronze players just gather mid for ARAM. Push out top and bot (without getting caught) and get that farm. Then look for opportunities to kill enemy squishes and just snowball the game with your item lead.
I have done it many times in the past and would love to carry out some bronze games again. But that requires leveling another account/throwing placements and then playing with toxic teammates. Which is work, unethical, and gives me a headache/would make me an asshole and I don't want to be an asshole anymore. Just focus on having fun and laughing at how bad everyone is around you. Use playing through bronze as a good time to buff your stats. I remember in season 4 or 5 I had an account in bronze where I just played random adcs on. I was averaging 25 kills a game with
before the adc update, which I thought was hilarious and had a lot of fun doing.