Play the piece "Heart and Soul" with the computer. Clicking the green flag will take you through a brief warmup. You can just click on the bear to skip that and start playing. You'll need to play four chords for the introduction before you start hearing the melody.
Heart and Soul was written by Hoagland Howard "Hoagy" Carmichael. The images are from https://www.rawpixel.com. I tried to make this mobile friendly. Please experiment with the different chords. For fun you might want to try different chords in the piece. For example the E minor and D minor chords could be used in place of the A minor chord and the B Dim chord could be used in place of the G Major chord.