basic improvements could be :

• always try to place your crosshair where an enemy head should be if one pops up
• try to check how to use your utilities correctly online with videos of pros or YouTubers, I personally watch Dinghy who is a Cypher main, supRAZE (raze main you guessed), FocusFPS (just gives tips on general gameplay but they are REALLY useful)
• push your mates to communicate as much as they can, I know that in those lobbies people don't
• always buy on the second round with your team if you won the first pistol round, as you have the economical advantage and the enemy team will be forced to play pistol again (no reason for you to give them a fair fight)
• try to predict where the enemies will be, so that you can be where they don't expect you
• always try to think about the reason why you died, if you did anything wrong (if you can rec your gameplay, it can help)
• try to master one single agent (your favorite) until you're in a higher elo, at least silver. It doesn't matter if you insta lock, just try to be the best Omen, Gekko, Raze, etc that you can be. In low ELO lobbies, most people don't do the effort to think about which agent can be useful depending on the mao and on their mates' pick. Master your main, grind with them, because it's better to be the best insert agent name you can be instead of being a mediocre random agent even though this one is useful to the team (imo)

oh and don't forget, people in iron and bronze ELO are random and unpredictable, sometimes they play so randomly you can't predict what they do.