Hi SteelCityAnne,
As we understand it, you want to know if you can move audio from the Files app into the Music app. Is that right? We're happy to assist.
As it's not possible to move content to the Music app from the Files app, you'd need to look at other options if you wanted to play that audio file in the Music app. Your best bet would be to use a computer, where you could download the file using iCloud Drive and then possibly sync it to your phone.
This covers how to Access and manage your files in iCloud Drive. The steps would depend on whether you have access to a Mac or a PC.
Once you’ve transferred the audio file from iCloud Drive to your computer, you’ll need to import it into the Music app or iTunes:
Import music from a computer to Music on Mac - Apple Support
Import media from a computer to iTunes on PC - Apple Support
You can then use these steps to Sync music between your Mac and iPhone, iPad, or iPod touch or Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support
Best wishes.