Here is a my relatively easy fingerstyle arrangement of the main theme of J.S. Bach’s beautiful melody “Sheep May Safely Graze.” It is set in the key of G, standard tuning. To play it in the original key of B-flat, capo it at III.
One challenging “stretch” fingering occurs in measure 3: an F#dim chord over a droning G in the bass. (You can think of this as a D7 chord with G in the bass.) Finger the sixth string in that passage with your ring finger, and the fourth-fret note with your little finger.