After you transfer files, you need a music player. Samsung offers the "Samsung music" player in the Samsung app store which is novelty good. It should auto import any music files you have.
I actually use itunes and transfer to my S20. Super easy. All of your music should be in files, and if you ripped cds they'll all be organized by artists or albums I believe in your music or itunes folder. Plug in the S20 and drag and drop those files to the media/music folder on the S20. Mine may be a bit different because I keep all my music on the SD card so I think mine is named media whereas yours might be named music. Hope that helps.