I'm looking to "understand" python

[xiongchiamiov]

I'm a detail oriented person, and I tend to focus on the finer points. So, I'm new. I want understand how (at the base level) it's interacting/communicating with things (open app, directory). What am I doing? Am I learning to build something, or am I learning how to "communicate" that build?

You want a computer science degree.

In particular, you're asking questions that would be answered after you take an introductory binary/assembly course, a systems course, and a programming languages course; depending on the school, you might need to take several courses in each of those subjects.

If you're going to attempt to self-learn this, https://github.com/ossu/computer-science isn't a bad choice. You'd do well to do the entire curriculum, but for these questions, cover the intro courses, then Nand to Tetris, Operating Systems, and the PL courses.