[BetterRed]

@Chapter One - if you don't have Mark Books in the Main Toolbar then use Preferences->Toolbars to add it to the tool bar.

Now browse your library and Mark the "Favourite" books (ctrl+M - note this is a toggle). When you're done use the Show Marked Books option (ctrl/shift+M) to list the Marked books, select all the marked books (ctrl+a) and use Bulk Metadata Edit (E) to update the Favourites column.

Important : The Marks are transient, i.e. they will disappear automatically when you close calibre. There's also a Clear All Marked Books option in the Mark Books drop down menu.

BR