A link my instructor posted in Moodle doesn't work.
Inform your instructor.
Look closely at the link to see if you can uncover where it is supposed to go. Possibilities include typos, content hosted on another site may have moved to a different address, content from the library's eResources may not be linked with a permalink, etc. Clues within the link or the text accompanying the link may help you search and find the right resource.
If you have not heard from your instructor in a reasonable time or cannot find sufficient clues to locate the resource on your own, submit a ticket for Moodle Support. We will do our best to help.