[usgroup]

I’d call what you want to do “teach yourself maths as a foreign language”. It can very much be done because I did it.

If I could do it all again, I’d start with an old school Calculus course. E.g “Calculus” by Binmore . It’s a decent and well explained introduction to Calculus and Linear Algebra and it’s useful maths. You have to get a hang of thinking in maths and doing maths you find boring.

From here it depends on what you want to do. There’s more maths out there than there is time so you need goals.