OBS

Install the program "OBS" in the software center (located on the desktop). It will require a restart of your computer after installing.

In Sources, Add a source → choose display capture.
in settings, in Output, change the file type to .MP4 instead of .flk
Use the button "Start Recording", rather than "Start Streaming". Streaming is if you were to have a live streamed event streamed on a website like YouTube or Twitch, etc. Recording will give you a file you can upload to your course.

Or follow a guide online such as this one:

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