I just discovered the WordPress concept of a "network" of sites, and it sounds like that is what I need to do. That way I do not have to worry about forcing WP to allow posts on subpages, and I can just use the main blog page of each networked site.
I also installed FileZilla to use as my FTP manager, that allows me to make subfolders in my FTP, which seem to be the same thing as a sub directory for the server.
Now, when I go to my test subdirectory on a browers
onemanz.com/guitar, I get
The requested URL /guitar was not found on this server.
Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
So I will go into my WordPress and Dreamhost consoles and see if I can something to appear published on that directory.