How do I play an mp3 on my iPad? I'm not trained on iOS and my iPad 6th Gen is the only Apple product I own.

iOS version is 13.3.
I have downloaded the app called, "Music"
I have downloaded Readdle Documents.

Using Documents, I have downloaded an mp3 file.  Now I'm not sure how to get the Music app to "see" it.
It seems like I need to add it to "Music's" Library, but cannot find the option to do so.

One solution I recall but can’t cite said to install an app called "iTunes", but I could not find it in the app store.  I did find "iTunes Store" but that seems to only be a way to purchase content.  


I am looking to use the content I already own.
I have no access to a desktop system that I can install software on, so any external or 3rd party tools are not accessible. 
I don’t know how I’ll bulk load mp3 as well since I lack a computer and readdle won’t let me manage playlists. 


Can someone get me started to how to play MP3?
Since you don't have a Mac, I suggest you start looking into third party music players like VLC, &quot;Cloud Music Player - Listener&quot; by Jhon Belle, &quot;Boom: Music Player and Equalizer&quot; by Global Delight Technologies Pvt. Ltd, Google Play music, &quot;Vox- MP3 &amp; FLAC music player&quot; by Coppertino Inc. etc.

What&#39;s a good iPhone app for playing MP3 music?

If a Mac can be used:

How to add podcasts manually to the new Podcasts.app on macOS Catalina



On your Mac, you can download audiobooks from Audible.com, then drag and drop them into Apple Books.

https://support.apple.com/en-in/HT208929#booklets