stay positive. if people are being negative dont use the chat. just do you, concentrate on your own game. be a positive influence on the team. ping a lot on where you are going on the map, objectives, enemy locations etc (intuitive pings). let people know youre placing wards in places especially if youre supporting. place wards (very important).
biggest thing is concentrate on your mechanical skills, map awareness (includes pings and warding), builds. if you really are a noob practice new champs in the bot games or in custom games. watch youtube videos. let people know when you bring it into a pvp game (most people are understanding and will give advice)
above all have fun and find people who will have fun with you that arent negative toxic jerks. dont pick up bad habits
edit: any champ can get you out of bronze if you get good at them. malzahar kept me in silver last season. im concentrating on supp thresh this season. i recommend sticking to a small pool to get good that you like. doesnt matter what people think is op.