This Lightroom Classic (LrC) series is intended to assist in finding information and help about using and understanding LrC rather than a full course, per se, on LrC. There are many free and paid resources for learning LrC, so there is no point in me reinventing the wheel so to speak. It is really a matter of how much of your time you want to invest in getting the most out of the software. Each of the topics will provide a brief overview and links for more information, detail and learning resources.
There have only been subtle changes in some functions of LrC and so those areas aren't covered as extensively: such as Map, Book, Slideshow and Web. Some modules haven't changed much but are important so have been dealt with in more detail: such as The Library and Print Modules. Most of the changes in recent versions have been in the Develop Module so a bit more detail and references are provided for it.