You have a handful of low-level languages listed. It doesn't make sense to try to put those through a JavaScript lens. Rather, pick one to start with and build

You have a handful of low-level languages listed. It doesn't make sense to try to put those through a JavaScript lens. Rather, pick one to start with and build some programs with it. You should quickly start to see how memory, I/O, etc, are handled. I would also recommend the book "Code: The Hidden Language of Computer Hardware and Software" by Charles Petzold as a general introduction.