Since you mentioned ML, I assume you'll need linear algebra (LA). I hated it for a long time since the notation abstracts away too many things. You can look at an equation involving matrices, but you cannot imagine how it would be coded. Unlike calculus where numerical approximations and code implementations are relatively obvious.
But I eventually needed to learn it as I have to code something not in Python/Matlab/etc as part of an app and would like to postpone using LA libraries unless absolutely needed for performance. What helped me get the grips on LA is Jeff Chasnov's lectures on youtube and Mike Cohen's book. I would also recommend 3blue1brown for appreciation, if he happens to cover the topic you wish to dive into.
But I eventually needed to learn it as I have to code something not in Python/Matlab/etc as part of an app and would like to postpone using LA libraries unless absolutely needed for performance. What helped me get the grips on LA is Jeff Chasnov's lectures on youtube and Mike Cohen's book. I would also recommend 3blue1brown for appreciation, if he happens to cover the topic you wish to dive into.
I'm many years older than you, by the way.