I want to delete a single document. How do you do this?
Do you really want to delete the document, or do you simply want it to disappear from the right pane of LibreOffice, which is shown when starting the application (i.e, from the recent document list)?
This is file management in your operating system, not LibreOffice.
There is some general advice on File management here including deleting files. Cheers, Al
You can use the dialog to open/save files, as these are usually fully working windows of the regular (file-) Explorer under windows. You can delete a marked file via context-menue (right-click) and selection of “delete/remove” or whatever a localized system may offer here.
On other OS usually similiar…
(It might sound strange to use open for delete, but as Windows had Start as entry for Shutdown it shouldn’t be surprising).