Comment by bvod

C++ is deep and nuanced, so reading books will help structure your learning. I've found Scott Meyer's books to be great for starting out. Those will give you a fantastic foundation, from which you can dive deeper. Those and others have added significantly to my ability to write clean and maintainable software.

This SO post is a great guide for where to look: https://stackoverflow.com/questions/388242/the-definitive-c-...