block for the navigation
Block


Define region in theme information file (https://www.drupal.org/node/171205).

Example: regions[main-menu] = Main Menu
Call the region in template file (html.tpl.php or page.tpl.php)

Example: &lt;?php print render($page['main-menu']); ?&gt;
Clear website cache

Procedure:  Configurations -&gt; Performance -&gt; Clear all caches
Now you can assign any block to the region.

Procedure: Structure -&gt; Blocks -&gt; Here you can see 'Main Menu' region as unassigned. Assign any block to this region (example: assign menu menu block to main menu region).


Templating

To know more about templating: https://www.drupal.org/documentation/theme

Since you are coming from a WordPress background, please get familiar with theme structure of Drupal and then start working on themeing.