Switch to ‘note entry’ mode
Click on the ‘N’ button to start entering notes, or use the keyboard shortcut with the “Control” and ‘n’ keys (Ctrl+n).
You then choose the duration of the notes (round, white, black, etc.) by clicking on the corresponding button with the mouse or using the keyboard: the ‘+’ and ‘-’ keys can be used to move from one duration to another.
Notes can then be entered either with the mouse or from the keyboard by typing on the letters (C, D, E, F, G, A, B) that will create the following notes (C, D, E, F, G, A, B)