In this video we see a basic exercise for basic jazz chords on the piano and also a scale. The chords that the pianist uses are Am7 – although he says Am9 in the video – and Bm7. These chords are repeated several times and then he adds CM7 chord (this is the chord that he says he doesn’t know what the name of it is). He plays a scale which he calls the D major scale without playing C#, but this actually would be G major scale, starting at the D note.
In music theory this scale would be called D mixolydian.
Although the terms that he uses in this video are not correct, this video is a good exercise for practicing jazz piano chords.