how do i publish the sandboxes shown in the vendor registration workspaces in visual builder studio?

Summary:

following the steps in the manual the workspaces are created, but when selecting the Sandbox the system shows in the list all of them in unpublished status, so it was not selected.

Question:

1. Was it necessary to select it? or can it be modified and selected later?

2. Is it necessary to select a sandbox from the list and which one would it be?

3. Where are these sandboxes located and how are they published?

4. When trying to clone from git the second workspace the manual indicates that you must select another sandbox called “Sites” that I suppose must be published. Same as point 2, where is it located and how is it published?