How Do You Put All BookmarksBar & BookmarksMenu Into One BookMark Folder?

Hi. My BookmarksBar & BookmarksMenu (some have save bookmarks, in them, some are empty. It's in a mess at the moment), looks like this:

How can I put all the links in the BookmarksMenu & BookmarksBar, including the bookmarks/links outside of those two folder, into one folder (either into the BookmarksBar or the BookmarksMenu)

Thank you in advance.

Gbu.