To jam and learn the simple chords for Reona - Nainai chords, practice playing C, Fm, Db, C, Eb, Ab, Db, Bbm and C in sequence. A strategic approach would be to train at 65 BPM initially, and then accelerate to the song's tempo of 130. Align the capo with your vocal depth and chord choice, bearing in mind the song's original key: Ab Major.