To do this, click on the course you want to update progress for, and go to the Users & Groups tab. From there, click on Bulk Actions at the top right.
In the new window, use the drop-down menu to choose what Status you want your learners to be changed to, then hit the Update Statuses button. This will change all of the enrolled learners to the chosen Status.
To learn how to make changes to multiple specific users simultaneously, click here.