Answer

Click on Discussions in your Canvas course to view the class discussions.  Then click on the name of a discussion to read the title and description. 

You are able to view replies, like them, and mark them as read by clicking on the three dots for options. If you are unable to view responses from other students, you may be required to make a reply before you can view them.  Once you reply to the discussion, any other replies will be visible.

To reply, click the Reply button and type the text and format it.  You can also insert media and attach files.

Visit this guide for detailed instructions on using the Canvas discussion board.