So with mice, you have a center position you return to after every move. From that position, ideally you should be able to turn your character between 270°- 180° degrees with a single swipe.
You'll want to use a mouse with an at least 1000 hz polling rate. They can be found online for less than $30. There are websites to test polling rates.
I recommend a DPI of 800. 1200± DPI will often make your sensitivity way to high, even if you lower the in game sensitivity. 400 DPI has more hitches.
Turn off mouse acceleration in windows.
Make sure the sensor in the mouse and the mouse pad is clean.
Lighting round: light weight mice are preferred. 8000hz is better that 1000hz polling, but not by much and uses a lot of CPU usage and requires correct USB support. Don't aim at the enemy, aim where they are going to be. Warming up a bit does help your aim. You don't need to spend a lot of money to get the best gear or to have fun.
Useful mouse comparisons. https://www.rtings.com/
There is a mouse pad compare website, but I can't find it.