Thanks for the video!
You can link to other markdown documents (or images) by either using relative paths, or absolute paths to that file. The only files it’s offering you are the ones in the same directory as the current file (all the 12_DEC files).
In the document you’re editing in that video, in the 12_DEC directory), I believe you’d probably want to begin by typing:
[some file](../11_NOV/202211 and then use the autocomplete shortcut. You could also start with .. and then use the shortcut.
It might be nice if Deepdwn considered all of the files it knows about regardless of the path, but I’m not sure how well that would work in practice.