How do i know which sensitivity to use for each type of scenario?

[gentle veldt]

I aim mostly with my Wrist and it feels jittery af and shaky, in cs2 i tend to microadjust with my wrist but i just overaim left and right also sometimes i feel like my aim/wrist just freezes and stop just before hitting the headshot, any advices?(41cm /360)

[lost pawn]

You should blend your arm, wrist, fingers all together. If you use mostly your wrist you've likely just been using faster sens which are more dominantly wrist. However, if you haven't and have been locking your movements with wrist (e.g. your forearm isn't on your desk, then you might want to change that).

Use arm for larger motions, and for added stability as a pivot for longer precise tracking.

You do not need to change your sens for each specific type of scenario. That is mostly what people do to optimize their scores or for preference sake.

[static kindle]

Sounds like you have an issue I had with shooting and aiming at the same time. I would be tracking towards my target but I'd stop whenever I shot. I fixed this by doing clustershot at a steady pace while nonstop shooting balls. So instead of flicking in clustershot, you should just find a smooth pace and just continuously shoot

[gentle veldt]

makes sense, sometimes i start shooting just before i reach the target