I create a custom module in Drupal 8. It install/uninstall smoothly. But when I try to access that module then I’m getting that message

"Page Not Found." -
Failed to load resource: the server responded with a status of 404 (Not Found)

For debuging I made these entries in my setting.php file.

error_reporting(E_ALL);
ini_set('display_errors', TRUE);
ini_set('display_startup_errors', TRUE);
$conf['error_level'] = 2;

But getting no luck. Is there any other ways to debug my code in drupal 8.

Here is my routing file code:

custom_module.admin:
  path: '/admin/custom_module'
  defaults:
    _controller: 'Drupalcustom_moduleCustomModuleController::custInformation'
    _title: 'Custom Module Title'
  requirements:
    _permission: 'access information'

custom_module.site_page:
  path: '/custom_module'
  defaults:
    _title: 'Custom Module Title'
    _controller: 'Drupalcustom_moduleCustomModuleController::custInformation'
  requirements:
    _permission: 'access information'

and link.menu.yml file code:

custom_module.admin:
  title: 'Custom Module Title'
  parent: system.admin
  description: 'Brief description.'
  route_name: custom_module.admin
custom_module.site_page:
  title: 'Custom Module Title'
  route_name: custom_module.site_page
  menu_name: footer
  enabled: 0

& controller file

namespace Drupalcustom_moduleController;

use DrupalCoreControllerControllerBase;

/**
 * Controller routines for contact routes.
 */
class CustomModuleController extends ControllerBase {

  /**
   * Render a list of entries in the database.
   */
  public function custInformation() {
    $header = array('Name');
        $rows[] = array("John");
    $content['table_brief'] = array(
      '#type' => 'table',
      '#header' => $header,
      '#rows' => $rows,
      '#empty' => t('No entries available.'),
    );
    return $content;
  }
}