HOWTOs are just what their title implies. They are meant as a reference as well as practical instructions on 'how to' do something.
The way to use these are to make your own copy and practice with the examples they provide. All the instructions are 'generic' in the sense that they can't hammer a nail for you, they can only show you how to swing the mallet. The 'HOWTO' may cover more than you need or want to know. Just ignore the part that goes beyond what you need. Each topic area are (mostly) organized in way that starts with the simplest (but maybe not the 'best' way) do to something and move on to more complex, but perhaps more flexible, options down the page.
Unlike pages with instructionals, these files are intended to stand alone. They are not presented in any particular order. Some of their topic areas overlap or are related to things presented in other files. For example, embedding images often only require a simple MarkDown tag but there are multiple ways to embed an image that can give greater flexibility. Navigating the range of options requires its own topic area.
Within a topic, each HOWTO tries to present increasing levels of detail as you move down within the example document. The goal is to try to be relevant to what is needed without presenting too much. As a consequence, these references are still a work in progress. Some of these areas of interest can be quite broad. Plotting data and Reading and writing from files are HUGE but effort has been made to distil it down to the basic needs for a classroom in a physical science or math class.