In order to track your progress in a course you need to start marking lessons as "completed." This happens in one of two ways. If the lesson is an article, video or assignment you can manually mark the lesson as completed by clicking on the "Mark Completed" button at the bottom of the page.
Quizzes are automatically marked completed when you submit them and achieve a grade of 80% or better.
When a lesson is marked as completed that box will turn green and will show the lesson as completed.
You can view your course completion status at any time just by looking at the right-hand side of the page when in a lesson. Here's an example:
You can then view a detailed chart of your progress by viewing a course home page, like this:
Or by viewing your progress in your "My Classroom" page. Not that My Classroom will only show tracks or courses that you are currently enrolled in.