Around 3:56 (in 3D Extrusion) the lecture addresses extruding along a path or in a direction. At least this student could not duplicate the shown exercise in AutoCad 2020 using comparable examples drawn by the student.
One wacky possibility is that the direction line or path has to be drawn in 2D (?!). How does one inject 2D into a 3D Model workspace?
Shifting from “3D Modeling” to “Drafting & Annotating” allowed me to draw a direction line or path. Alas, shifting back to “3D Modeling” and invoking extrusion did not work. “Extrude” requested the start and end in either direction or path modes but did nothing.
Making lines along the 3D plane is not possible without changing the UCS which is discussed in the 5th module “Visualizing solids” first topic “Understanding user coordinate system”. For now, I would recommend the student follows the lesson files which are provided at the beginning of the course. They can easily replicate the command using the lesson files.
The version has nothing to do with this tool as from 2017 up to the latest version there is hardly any change in the 3D environment or tools of AutoCAD. Once they are done with module 5 they will be able to make their own sketches in the 3D environment too.