The bottom Tablature

Okay, I've googled this a bit. Even watched a video where a young lady was explaining how to play each.Take a look at the linked pdf.

I understand how to play the top half. I understand how to play the bottom half.

What I'm not quite grasping is do they get played together somehow?

Or is this just a one or the other thing?  Thanks.

https://www.dulcimertab.com/wp-content/uploads/tab/will_the_circle_be_unbroken2.pdf