how do i delete a playlist in apple music but not the songs

Hello,

First you would need to add the individual songs to you library before deleting the playlist. You can make this easier by automatically adding songs from playlists to your library.

Add music to iPhone and listen offline - Apple Support

"When viewing the contents of an album or playlist, tap  near the top of the screen to add the album or playlist, or tap , then tap Add to Library to add individual songs."

Create playlists on iPhone - Apple Support

"Tip: If you want to add songs to your library when you add them to a playlist, go to Settings > Music, then turn on Add Playlist Songs."

I hope this helps.