This lesson comes from my Method Book Volume 2.
Below is the lesson for C Major (Page 7) including the scales and chord progressions. The lesson for the Menuet by Rameau (Page 8) starts 6:30 mins. The lesson for Vals by Carulli on (Page 9) starts at 7:25. Be sure to watch the whole video straight through to get an overview and to not miss any info.
Below is a recording of the duet with my friend Natasha Pashchenko as well as the chord song Morning Has Broken (Page 10). Please note that the updated version of my book does not use slurs in the Menuet so disregard the slurs and follow the above lesson for your practicing. If you are playing the duet without a teacher just play the top line on its own.