[derbOac]

"Memory as a Programming Concept in C and C++" was a helpful book for me. I'd stick to C as C++ is kinda kludgy syntactically with higher level constructs and they're not key to lower-level stuff anyway.

After that, you might look into Rust. I don't have any particular recommendations; there was/is an introductory text online by the original Rust developer I found helpful. Rust is sort of hyped the last few years, but there's good reason for it, and its approach to memory builds well on classic C-like ideas.