Assigning a Training with a Due Date allows Managers (and above) to require their users to complete a Training within a certain time period. To successfully complete or finish a Training, a user must view all Modules in the Training and pass all associated quizzes.
Note: The Training creator has the option to create either a sequential or non-sequential Training. However, all Modules must be viewed, along with quizzes, in order to successfully complete a Training.
Once you've completed a Training, you can always return to it by clicking on the completed Training. It will appear just like any other Training, except when you click into it, you'll see that all of the modules have been "checked" meaning you've completed them.
We hope that helps! If there's anything we can clarify or help with, please let us know!