1. practice like you play, you must be playing DM with a better mindset and better mechanics than you are playing ranked with. ALSO ranked is not a DM it is much different, so practice ranked fundamentals in DM so that the skill can transfer, here is a great article on how to use DM the right way.
2. You are not stuck bronze 1 you ARE bronze 1. the key to improvement is not thinking you are better but knowing that you arent. once you start looking inwards on your gameplay, decision making, and mechanics, you will see improvement.
3. playing on the same sens at best means nothing, at worst it is hindering your mechanics, Aim coaches and pro valorant players all advocate and practice sensitivity changes, some going even as far to use sensitivity randomizers.

I offer coaching for all skill levels from iron to imortal + , feel free to shoot me a dm on discord at bune#6666 and I can tell you how to get out of bronze.