u/TamoThePirate

In tracks or albums you can select how ever many items you want and click add to Playlist.

In files there is no option to add the entire file to a Playlist. You can select 1 song and add it but not multiple.

I have multiple file folders on my phone with over a thousand songs and I usaly just add those to a Playlist on other apps.

FIXED: I clicked 'create smart Playlist' then 'tracks' then 'add rule' then 'path and file' then under 'filter value' copy and paste your file folder name then click save.