If that's the Get Album Artwork command, there does not seem to be an equivalent command in the menu bar that applies to a single song (or a selection of songs). Not in the main menu bar or anywhere else. The command in the menu bar for File -> Library -> Get Album Artwork is available, but that action applies to your whole library.
However, if you put your music library into Albums view (to show the view with album artwork "tiles" in a grid), I noticed that you can right-click on an album and Get Album Artwork. I think that applies to all songs on the selected album (or albums). I suppose that makes "some" sense, since missing album artwork is usually for all songs on the album.