From the keyboard, { Ctrl + B }.

You can organize your bookmarks in folders to prevent having them in one long list. You can create folders anywhere in one of the three main bookmarks folders (Bookmarks Toolbar folder, Bookmarks Menu folder, Other Bookmarks) depending on where you want to see them.

• https://support.mozilla.org/kb/bookmark-folders-organize-your-bookmarks

If you click the star on the Navigation Toolbar then the new bookmark is stored in "Other Bookmarks", but the panel opens automatically and you can move the bookmark to another folder. The "Show your bookmarks" next to the star opens a vertical bookmarks list. You can also open the bookmarks in the sidebar (View Bookmarks Sidebar) to have a vertical list.

What do you mean with save it as a tab?

A bookmarks is a link to a page on a website. If you click this bookmark link then you open the link in a tab. Bookmarks you create on the Bookmarks Toolbar are listed horizontally. This is true for bookmarks and for folders, so you can create some folders on the Bookmarks Toolbar and save bookmarks in these folders to have them appear vertically when you click a folder icon.

Do I have all of the following correct:

-Clicking the Bookmark Star and saving a bookmark in the 'Bookmark Toolbar' folder places that bookmark on the horizontal bar below the URL 'and' displays it in the 'Bookmark Toolbar' folder vertical drop-down list under the Bookmark Header

- Clicking the Bookmark Star and saving a bookmark in the 'Other Bookmarks' folder only displays it in the 'Other Bookmarks' folder vertical drop-down list under the Bookmark Header..

- Clicking the Bookmark Star and saving a bookmark in the 'Bookmark Menu' folder only displays it in the vertical list under the Bookmark header

d) Clicking the 'Share Data' green box, displays my Firefox Version , OS, and installed plug-ins for anyone reading the thread to assist me better.

You can try it out yourself and click the Choose button in the "Edit This Bookmark" dialog that opens if you click the blue highlighted star. If the bookmarked page is open in a tab then you can easily move the bookmark around through various folders. That way you also get more grip on how bookmarking works. On the Bookmarks Toolbar you can easily create a folder via the right-click context menu or simply drag a bookmark with the left mouse button held down to an existing bookmarks folder.