In the minute 6:30 it teaches how to include a circle, but my version of blender already creates a circle vinculate to the cilinder, this mean all the functions already set before come vinculate to the creation of the circle ( duplication ). And I need to desvinculate these two figures to create my new one.
Select a single vertex of the circle and press Ctrl + L, which is the shortcut to select all connected geometry. Once the circle geometry is selected you can press P and then select “Selection” to separate it to a new object. I recommend resetting the origin of the circle to its center once separated, you can do that by selecting it in object mode and pressing W, then navigate to the “Set Origin” menu and selecting “Origin to Geometry”.