You might take a course on linear-algebra, at K.A. for example:

https://www.khanacademy.org/math/linear-algebra

And any prereqs you need. I also find the math-is-fun site to be excellent when I need to brush up on something from long ago and want a concise explanation. i.e. A 10 minute review, more than a few pithy sentences, yet less than a dozen-hour diatribe.

https://www.mathsisfun.com/

Thank you for sharing this!