How should I start learning low-level programming and networking?

C is a sensible foundation for understanding operating systems, but C++ or Rust can also be valuable depending on the projects you want to work on. Rather than waiting until you have mastered one language, choose a small open-source project, study how it works, and make improvements or fixes. Working with real code will teach you how to read unfamiliar codebases, use version control, test changes, and collaborate—skills that matter just as much as the language itself.

For your interests, C and Linux are a strong starting point. Learn C thoroughly enough to understand pointers, memory management, structs, function pointers, compilation and linking, stack versus heap usage, and debugging with tools such as gdb and sanitizers. At the same time, become comfortable using Linux: the command line, processes, files, permissions, pipes, signals, system calls, and shell scripts. Build small projects instead of only reading tutorials—try a basic shell, TCP or UDP client and server, HTTP server, socket-based chat program, memory allocator, multithreaded application, or file-indexing tool. Study networking fundamentals such as TCP/IP, DNS, HTTP, routing, ports, and packet flow, using tools like Wireshark to see what is happening. Once those foundations are solid, explore Unix and kernel internals and look for small documentation, testing, or well-scoped code contributions. Kernel development is a long and difficult path, so don’t expect major contributions quickly, but each project will build useful experience.