Hi there, @KatherineJensik ...
Super easy! You can configure your Canvas account to get notified about discussion replies by following the instructions in this Guide ... which is for your entire Canvas account as a whole:
Also, you can configure your notification settings per course...if you prefer to do it that way:
In addition, if you want to add additional e-mail addresses to your Canvas account ... so that you can also get notified about discussion replies to those e-mail addresses, too ... you can do that via the "Settings" page of your courses:
Once you add one or more additional e-mail addresses to your Canvas account, then you can return to your "Notifications" screen, and you will see those e-mail addresses displayed as new columns where you can then set the frequency of how you want to get notified.
I hope this will help a bit. Sing out if you have any other questions about this...thanks!