Before you begin deleting the duplicates from the list, see if the same song may be from different albums.
You wouldn’t want to delete a blistering song off of a live album, for example, and keep only the studio version.
After adding music from to your i Tunes library, the first order of business is to find and eradicate duplicates.
In Detail view, check the box along the left edge to select files.
With a file or files selected, a Download option appears in the menu at the top of the page.
To avoid such an occurrence, click the Same Album button centered at the top of the list.
Now the list will show you duplicates that are only on the same album.