But that's mostly learning modern paradigms of the language.
If you also mean the tooling, then it depends: Learn CMake which is sort of an industry standard. There are books and videos, but for a concrete experience, try looking through the CMakeLists.txt of some non-trivial C++ open source project.
Probably the best resource for CMake modern best practices/ rational of those practices.
Most tutorials online are outdated, CMake documentation is hard without a firm mental model of how it works.
You say that like there's one for a project but I've been learning Blender's codebase and every folder has a CMakeLists.txt. What gives?
Use clangd, clang-tidy, cppcheck. (These will tell at you if not using best practices)
Use the stl as much as possible (or at least make "would this work using stl" your go-to question.
Write a vector with iterators from scratch in c++20