No, at no point should you use the standard library to understand how to write C++ code. The standard library has a specific clause in the C++ standard that exempts it from rules about undefined behavior. For example, that link I pasted to implement a std::vector is not something that is permissible to use by non-standard library code, it is full of undefined behavior that is permissible for use by the standard library but not permissible for use by ordinary code.

To the extent that one can learn how to write cross-platform efficient and generic C++ code, there is always a better example to learn from than the standard library.