A blank page will open up.
Whenever we encounter new software or new places, we tend to focus on what looks different or strange. Instead, focus on what looks familiar here.
At the top of the page you'll see:
You know these from dealing with Word and other document processing software.
At the bottom of the page, you might see a series of boxes and command buttons. Some of these should look familiar as well.
With luck you're feeling a bit more comfortable in this new land of Dreamweaver.