Tools Pane

A Navigation Pane displays only one tool at a time. Other tools are collapsed and their buttons are displayed at the top of the panel.

You can use the options to set the pane docked to either left or right side of the feature's main window.
To expands the page and show the tool click on a page button with tool, also you can click on the same button located on the main feature toolbar.

Also, you can expand and collapse the Navigation Pane using the corresponding buttons at a page’s top right corner.
 

There are two buttons:

Fill
Expands the page to fill the entire area of window, the second click collapses the pane to previous size

 
Collapse

Collapses the page and hides the tool.

 
To resize expanded page you can also drag the page side border in left or right direction

You can use any tool from navigation page as a separate window.

Separate Windows are the pages from the navigation pane that can be opened within the main area of main feature window.
By checking or unchecking this options the pages can be moved to the main area and back to the navigation pane.
After you will have some of pages moved to the main window area you can further move them around the window as is described in Docking Windows topic.