The task of extracting audio from video may seem daunting, but it really isn't.
For this you need:
1. Install MyMp3 app.
2. Launch it and click on the magnifying glass icon on the top right.
3. Click “Choose video from gallery”.
4. Select the video you want to extract audio from.
5. Click on the three dots and chose "Open with".
6. Select "Save to Files".
The extracted audio will be in MP3 format. This way you will be able to play the file anywhere.