music files on new android phone

Hello,

I recently switched from iPhone to Galaxy z flip 3. I can play mp3 files directly from a usb drive, one at a time manually. I can't figure out how to play several files automatically. I would also like to add files directly to the phone's internal storage; nothing I have tried has worked so far. Any help will be appreciated.

Also, it has been mighty slow-going for me on Level 4 but I hope to complete it by the end of the year. Suggestions? Encouragement? I have the first 2 choruses of Gary's Blues under control, choruses 3-4 are coming along, haven't started chorus 5 yet. Any comments will be appreciated.

Oh, I stumbled onto a YouTube video of someone playing The Strut, which is one of the required study songs for Level 4. Check it out, inspiring. Here is the link:

https://www.youtube.com/watch?v=WtTMCKFkBOQ&ab_channel=Seelien

Hank H