Hi Pablo eelTurbo ,
Grease Pencil has been totally re-written since this Course. The Curve Edit function, is now no longer a Selection Button, but I think you need to switch the Curve Type here:

Also note Omar's response; Blender changes really fast! It often takes longer to produce a quality Course, than for Blender to bring out a new Version. And Timestamps and Screenshots can really help in solving a question.