You know you are done entering W-2 information when
All of the information from your W-2 has been entered into that W-2 page.
When all of that is complete then at the bottom of the page you have a choice to either
Go back ( which does not save your W-2 Information) or
Continue (which saves your W-2 Information)
Then you have the option to Add a W-2 or
Done
I hope this helps
