True Beauty of Math Volumes I and II. These build up math from the ground up starting with sets and assume you have zero knowledge of math. What's cool is that you don't use any theorems, structures, or notation that you haven't proven or introduced previously in one of the books. I've found them to be very valuable in both understanding the topics that they cover and giving an intuitive understanding of math as process (which the all the classes I took in college tended to gloss over).

The first volume is roughly about set theory and the second volume is roughly about abstract algebra.

https://truebeautyofmath.com/

https://www.amazon.com/True-Beauty-Math-Foundations/dp/15120...

https://www.amazon.com/True-Beauty-Math-Giving-Life/dp/15448...