I have uploaded all my music and epubs to iCloud-drive in different folders.
For books to be added to iBooks I had to select one book at a time and then select option Copy to iBooks and now the books are appearing in iBooks.
Similarly I tried for my audios which plays from iCloud-drive app but I don't see any similar feature to add it to the Music app library so that I can use the features of the Music app like playlists and all. Also I don't see any option in Music-app to add music from iCloud-drive.
I am using latest iPad with iOS-11.
Any help would be much appreciated. Thank you.