Hi, Cesar.
You filed this under “General Discussion”, so we can’t tell which course you are talking about. But just looking at the error messages, it looks like you are running locally on your own computer instead of on the course website. If you do that, you need to bring down more than just the notebook itself: in most of the courses here, the assignments include a whole tree of files with the notebooks for each assignment. Here’s a thread which shows how to download all the files for a given assignment.