All of primary school pretty much trains you for calculus. If you didn't pay attention in trig class and didn't learn wtf a unit circle was, you are gonna have a bad time. The thing is, calculus is easy as fuck to understand, yet as always, shit teachers gotta make shit complicated as hell to make themselves feel superior to their students. Stuff like learning the unit circle takes like 10 min to learn. It is even easier today with youtube and all the homework help sites out there.

One of my majors was math, and as a dude who was completely shit at math when he started college (I didn't even know how to add fractions, lol), I gotta say the best way to progress on the subject is to practice in your free time. I'm also gonna tell you a secret: math majors are thought as hardworking nerds, but honestly the workload was a shitton less than any other major. You just need to be able to understand what you don't know and learn that on your own. Once you get things to click, homework takes like an hour tops. Sure as hell beats doing research for a fucking week, reading through a ton of papers and then stressing over a paper. All my math papers were purely logic based and the only citations I needed to make was references to the textbook. While my friends in other majors were stressing the fuck out during final weeks, I was just sitting there silently agreeing with them while I spent my nights shitposting on the internet and playing video because I didn't have jack-shit to do. Then when you graduate, you can apply to just about any technical job because people think you are a wizard. Math being hard is the biggest scam of the millennium.