@SR-Coker We will try to help. It looks like you'll only be able to leave feedback for Chris' lesson 27 and onward due to updates to the Weight Loss course.
When you submit your feedback, Chris should receive an email alerting her that she has feedback waiting, but you might also want to alert her yourself. She will be able to view her completed lessons with your feedback by using the outline icon in the top right corner of the course homepage to select the lesson and step she wants to view. She will be able to move forward through the lesson reading your comments to her answers by using the arrows at the bottom of the page.
We hope this helps.