Open mic nights at your local bar are a great source of data. Approach people after their performance, compliment them, and ask them if they have a coach they'd be willing recommend.
https://completevocalinstitute.com/complete-vocal-technique/
Their work includes pedagogical research to develop a consistent terminology which abandons lots of outdated and confusing terms such as you mention. No more ambiguous words like "project" or "space" or "support".
Their research also includes using endosciopic cameras to directly observe the vocal tracts of professional singers.
I've not actually trained with them, I just like their research and approach.
I also agree that the linked page isn't useful, it's more of a glossary than anything, but then again, I'm not convinced that a distinction between head voice and chest voice actually exists. I've never been able to tell any qualitative difference, as opposed to, for example, falsetto, and the community can't really agree on whether they actually are a thing or not.