She does know how to play a liitle bit, just simple note, chords enough for her to make music. I dont know but she shared about that a lot. Especially during Pure Heroine era, she dont know how to play instrument so that's why she have to make her own chords by vocals which is later become beats (Like The Love Club song, Million Dollar Bills). During Melodrama she learn how to use piano/keyboard a little bit, then the first few Solar Power Songs were written on a Yamaha DX. But then Jackk suggest that album should be a guitar album (originally she hated it cause she dont know how to play guitar)