You might check with the college to see if it's possible to test (or re-test) out of remedial courses. If the answer is yes, buckle down with old textbooks, the local library, YouTube, free online courses, local tutors and whatever else you need.
The one caveat here is if you're taking more math courses later, you really need to get these basics down, because the later courses will build off of this content. So don't just "study for the test" and then forget it, try to really understand what you're doing and why.
A couple comments, from personal experience: first off, there are different ways to teach math. I've had teachers who explained something so beautifully and clearly that, if I happened to forget a formula, I could remember the explanation and recreate the formula. And I've had teachers that were teaching me stuff I already knew cold, who had me so confused on the stuff I definitely already knew, that I had to switch sections before they hit stuff I didn't know. Do you might need to look at a different book or course or something, if it doesn't make sense to you.
Second, when they assign a handful of problems out of the back of the chapter, don't do just those problems. Do every single exercise in the back of the chapter, and check yourself when you complete each one. If it's the wrong answer, do it again. If it's still the wrong answer, keep going until you get the right answer, but pay attention to what you're doing: you have some basic misunderstanding of what you're supposed to be doing, and you want to identify and correct that misunderstanding so it doesn't screw you over later. Math builds on math; if your foundation is shaky, you're going to collapse when you get to the upper levels.