Climbing for me seems impossible

A quick glance at your most played champs and guessing at your play style, I would suggest Thresh or Braum. They will allow you to be tanky, melee, and allow a bit more poke/gap closers.

You're playing support, that's why you can't get out of bronze. IMO top lane/adc is probably the best roles to gain elo

You don't climb out of Bronze as support unless you duo with an ADC.

u wont get out of bronze unless u get good teams. i have a friend who is g5 and always feeds. he literally climbs by feeding. its how this ranked system works. from bronze to high gold its like 90% luck and 10% skill

You play ap brand and u don't play him as a support. Go full mage.

The problem is that people do the same thing game after game and expect different results. To climb, you have to be the reason your team wins.

Some games your team will do well, and other games your team will do poorly. if you win the games where your team does well and lose the games your team does poorly, you will stay where you are. You have to be able to win games where the rest of your team did poorly.

You don't even have all your tier 3 runes yet, and your experience is spread across too many champs. You are not ready to advance until you straighten your runes and masteries out and focus on the champs you are good at.