New Test Parent Category
You do not have a link list or collection with a handle set to new-test-parent-category, or you do and it's empty.
Go ahead and create a link list called New Test Parent Category on your Navigation page and populate that link list with links that point to collections, to see collections listed here. Make sure the link list also has a handle set to new-test-parent-category.
OR if you want this page to be display products, create a collection called New Test Parent Category.