For what it’s worth, I was an EE in school with only three half assed programming courses, one of which was ASM, and now I spend all day writing C++ applied in a super interesting way. What you want to accomplish is doable, and having an engineering math background is a huge leg up over the typical CS grad if you can work past CS fundamentals yourself.

The fields I'm mostly interested in are RF, Signals Processing, and Controls

Then take RF electronics, DSP and a controls class. You can’t program in these areas without knowing the basic theory.

Beyond that, toss out Python for now, as an EE you’re probably smart enough to do the thing properly without taking a lot of time to ease into it.

Learn C well (you can find a free copy online). It is a small language, and the book is less than 200 pages, but will set the stage to go into nearly any area of CS that you want, as it interfaces with hardware and memory management rather than sweeping it under the rug like Python.

You will get to the point where you automatically start thinking about how you might implement higher level abstractions (again, like Python) in C whenever you encounter them. Which most of them fundamentally are.

become a better engineer

Rather than focus on how things are done, ask why they were done that way.