You'll quickly see the Dropbox folder, and have the option to choose
subfolders inside as well.
That lawyer arbitrarily creates and names
subfolders inside his or her personal folder.
If the latter, I suggest «eBooks» as
a subfolder inside your «Documents» directory.
Place your media content in the appropriate
subfolder inside the main Plex folder inside Files.
Not exact matches
Inside the Plex folder,
subfolders corresponding to the different library types that Plex supports will automatically be created (such as Shared TV Shows).