It'll help you in the long run. People usually learn about this on some video game forum (like OSU! or some RTS game) but it has benefits in general computer usage too.
Windows and other operating systems apply mouse acceleration by default. What this means is that your cursor doesn't move the same amount of pixels when you move your physical mouse the same distance. For example, if you move your mouse an inch slowly, the cursor might move 50 pixels or so. Then if you move your mouse an inch very fast, the cursor will jump like 400 pixels. Because the acceleration of your physical movement affects the speed of the cursor.
Why this is bad is that it removes any and all chance you have of developing muscle memory. Why this exists is that it helps people who rarely use a mouse to be more accurate. Because when you're fumbling with something you usually try it slower and then the cursor goes slower. But turning off mouse acceleration will let you develop muscle memory so you don't have to go slow. You will just be able to click on things without thinking about it.
On Windows, search for mouse settings, open the settings app, click on the blue "additional mouse settings" link on the right and go on the tab that has the mouse speed slider and then uncheck the checkbox that says "improve cursor accuracy". It'll feel weird at first but once you get used to it you'll thank me.
Also do not move the mouse speed slider. It fucks with the mouse speed even more. Just keep it at the middle where it is by default. If you want to change the speed of your mouse use your mouses configuration software. If your mouse doesn't have any software, try to get used to it or get a mouse that has software. Like a Logitech g305. The absolute cheapest Logitechs don't have software. Razer is a shite brand. Logitech has the best sensors and wireless dongles and usable software. Can't recommend anything else.
Also also if you're using a mouse with adjustable DPI (dots per inch, it's basically the real speed of the mouse) and you're using something over 1600+ then reconsider. I use 800. I wouldn't recommend anything above 1400 for normal people. And remember, this is at the Windows cursor speed slider at the default, middle value. If < 1400 DPI is too slow for you, clear more space for your mouse, get a desk mat (not mouse pad) and get used to it.
Additional nerd talk
If this sparked your interest and you're wondering if this is why you suck at FPS games, I'm sorry, it's not. At least not anymore. Twenty years ago games used to take input through the Windows shell but nowadays almost all games (even the ones that have a cursor) capture input directly. This is sometimes called "raw input". The reason why you suck at FPS games is that you're not a 16 year old with perfect reflexes who's been playing the same game for half of their life.
If you play a lot of competitive FPS games, you should look into tools like Mouse Sensitivity Converter to match the sensitivity of your different games. It's also generally good to have a sensitivity where half of your keyboard equals about a 180 degree turn in-game. This also depends on the game and if you play a lot of very different speed games like CS:GO and Apex Legends you'll basically have to have a faster sensitivity on Apex.
Also I don't really know shit about FPS games and I generally suck at them, this is just what the people in my life who are actually good at them have told me over the years.
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