is it just if you get the concept you don't forget it? Like riding a bike?

it's all this.

I just find it hard because all the things I need to remember have these complicated.. terms?

Like say I understand finding the derivative of the inverse function. Sure I can read it do some problems and understand it.. but what I'm actually understanding and memorizing is the way a couple of lines look on a graph? And it's so hard to understand something so... Weird is the best word I can come up with.

I learn one way that a line moves, I learn how it might intersect with the x axis, I learn how a function can be bounded above and then below and then I need to memorize how to say it formally.. and then all I've done is look at a way a line moves. Idk it's so hard for me to understand things that is so arbitrary and general.