Hi there, @KarlaHarris ...
Based on your question, I assume that you are an instructor? If that is the case, I would suggest watching the following video tutorial:
Then, if you wanted, you could watch this one which is geared towards students:
Finally, if you wanted to take a deeper dive into how Discussions work in Canvas, there are a lot of written Guides that cover many topics:
- Instructor Guide - Instructure Community (canvaslms.com)
- Student Guide - Instructure Community (canvaslms.com)
Also, this video is a good extra resource as well:
Hopefully these links will be helpful to you.