Streaming music by genre to Flutter Mobile application

I have a music player in flutter that plays a song from a link like so.

await audio.setUrl('');

This works great, but it is quite limited for the intended functionality. I would like to continuously play songs from a selected genre. So if a user were to select country music, the app would pull random songs from the country genre. Is there any service/ api/ workflow I can implement to get this functionality.

I tried using the Spotify api but I would like something a little more beginner friendly.