Which is the best free C++ course?

Learn Advanced C++ Programming (Udemy) It is a great choice for those who know the basics of C++ and want to advance their knowledge to the next level . Also it is very handy for those who know the older versions of C++ (like C++ 98 or before) and want to explore the new features introduced in C++ 11.4 Mar 2022

How to Learn C++ Programming: 6 Sites to Get Started