This sounds like me a bit. I'm 40. I've worked as a programmer for 15 years, but I've always known my lack of maths is holding me back abd adds to my imposter syndrome. I've decided the new programming language I'm learning is, well maths. I'm just working through khan academy. I'll give myself this year's free(ish) time. I've got a family and a job, but I need to feel some sense of progression. I ll see what happens.
I like maths but I'm a CompSci first. Going to full-math mode is not easy after years without practicing. For example, the first 6 months, I spent a lot of time bringing back memories of basic stuff. In my case : probability calculus (the very basic stuff, expecations, conditional probabilities, etc.), Bayes theorem, least square derivations, Lagrangian, linear algebra, simplex method.
Be sure to reach a teacher at some point because these "simple" things are actually quite fundamental and thus sometimes hard to grab.
After that I can understand more complex stuff: GAN's, GLM's, SVM's, PCA, you name it... Things that were totally alien to me 1.5 years ago.
But well, just do it, in any case you'll be better! And proud of yourself!
