Thanks very much for the additional information about other sources.
My apologies for not being clear about " posting and maintaining a list of such resources". I meant to say that it would be ideal to have such a list as a part of the Affinity resources: tech support pages, forums, etc. For the reasons that you list: distinguishing between "edit", "develop", "image processing", etc., the process of searching these parameters is time consuming and the search results are dependent on a number of variables. Then there is the need to separate the good from the bad. All of it is very time consuming.
IMHO, I think it would be a fantastic resource for the Affinity community of application users to have a central reference source posted for their use. New and seasoned Affinity software users all face the learning curve associated with whatever Affinity application they use. I think that for most users the primary goal is to create artistic output and to learn how to use the software as quickly and efficiently as possible. Reducing or eliminating the need to search for references, videos, text, etc, would smooth the process of learning the software. For instance, the references offered by everyone in this thread would ideally be added to a central reference repository for others in the future who have similar questions. Rather than spend time searching or having contributors repeat themselves, users could peruse the collection of contributions, organized by topic and software application -- one stop shopping, eliminating the need to wade through the internet. Let the wisdom and experience of the seasoned users be captured and shared in a central / organized fashion. Of course, the references would primarily target the various Affinity applications and not be an attempt to create an all encompassing knowledge base.
Admittedly, there is a part of me that likes to learn about "image processing", "developing", "editing", etc., just for its own sake. However, when my artistic side comes out, he wants a cool photograph ... not an exercise in reference research.
In any case, thanks for your input. I appreciate everyone's effort to help.