The notes on those holes are C,E,G on the blow and D,G,A on the draw, that is for 1,2,3.
They are designed to be played as chords, and we need to have our bending under control in order to play scales effectively on them. That’s why those holes are left out of the 1st position Major scale in the beginners course.
All will be revealed as you move through the lessons!
Hope that helps!