How Can I Become an Excellent C and C++ Programmer?

Build things instead of only reading about the languages. A project such as a password manager, command-line tool, HTTP server, or other practical application can teach you about libraries, architecture, debugging, security, and system design in addition to syntax.

A useful challenge is to build the same project in both languages. For example, creating an HTTP server in C with sockets and then implementing a C++ version with a suitable networking library can highlight the differences in design and idioms. For C++, studying a book such as Effective Modern C++ can also reveal habits that come from writing C-style code in C++.

There is no secret formula. Keep learning, apply what you learn to real problems, review what you built, and then repeat the process. Consistent practice over a long period is what makes the biggest difference.

Try not to treat C and C++ as a single language. They encourage different approaches and have different best practices. Choose a substantial project, build a first version, improve it, and use the result to identify what you need to learn next.

Practice regularly and deliberately. When you get stuck, investigate why, read documentation or quality code, and then revisit your own implementation. If you are unsure how to improve, set a concrete goal—such as learning memory management, templates, concurrency, testing, or performance—and build something that requires it.