Have a Discussion post to write and must embed a link, How????
Here is some great documentation provided by Canvas about how to add a link in your discussion post reply.
How do I link to a YouTube video in a discussion reply as a student?
How do I link to a YouTube video in a discussion reply as an instructor?
You have a couple options available - if your students can see the Discussions area (Discussions isn't grayed out on the left), then you're all set - students can get to the discussion already.
If you are using Modules, you can add it to a module: How do I add assignment types, pages, and files as module items?
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