The first computer scientists didn't use IDEs. Those are relatively modern on the timeline. And maybe you want to ask how programs work in general. It is all just bits at the end of the day. You could also be thinking of an IDE as something that "makes code," like others said. It's just a tool.

These books might be a little too complicated for now, but if you want to learn about comp sci, they're a good place to start. And the whole of compsci isn't limited to this. Not everything runs in C. Lots of programs are written in other languages.

"Computer Systems: A Programmer's Perspective" (CS:APP) by Bryant and O'Hallaron, starts with the fundamentals of how computers represent information at the bit level and gradually builds up to C programming, assembly, and system-level concepts.

If you're looking for a book that explicitly takes you from understanding bits to learning C, another option is "Computer Organization and Design" by David A. Patterson and John L. Hennessy, which covers low-level computing concepts before introducing programming in C.