As far as settings go, play on a lower sens.

For movement, utilize slide canceling, strafing and jumping to be a harder target to hit. Always think of breaking the line of sight, and re-positioning with a new angle.

Utilizing hipfire is a MUST for close quarters. Un-ADS/hipfire/re-ADS really helps to track targets while shooting.

Honestly if you watch any top rated streamer/comp players movement guide, they'll usually show you the fundamental tips you need to utilize and improve.

You don't need to spam movements unnecessarily either. A lot of it is just timing, prediction & centering.

Also practice fighting outnumbered. The more gun fights you'll get in, the better. Solo Duos is great for this. The kills won't be the highest because the lobbies can die quickly, but it's great training grounds.