How do I get my music back to my Google Music Play app from my music files on my Galaxy S 7 Edge?

I originally downloaded the music on to my phone from an external hard drive and the music was there for a long amount of time. Then one day, it was gone and after doing a little navigating through the phone, I found it in my audio files for my Samsung Galaxy S7 Edge. How do I get the music back onto my Google Play app so I can enjoy listening to the music they way I want? Thank you for helping me with this problem in advance.

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/showthread.php?t=795311&goto=newpost
via IFTTT