How do I add a pagination on a template file?

Question

I'm currently new with Drupal 8 and right now I'm trying to output a pagination on my twig file using entity query. So far this is my current code that I came up with. My goal is output the news content type using entity and add a pagination. I've already added pager(9) to display only 9 items. I tried inserting {{pager}} on my twig file but I don't see any pagination being rendered. I'm not sure what I'm missing here. Really need some help.

// Entity Query for News
//////////////////////////////////////////////////


$newsPostings = $query->get('node')
    ->condition('status', 1, '=')
    ->condition('type', 'article')
    ->sort('created', 'desc')
    ->pager(9)
    ->execute();

foreach ($newsPostings as $key => $news_postings) {

    $newsNode = _nodeLoad($news_postings);


    $publishDate = strtotime($newsNode->get('created')->value);
    $articleCreated = date('F j, Y', $publishDate);


    $variables['article'][$key]['title'] = $newsNode->get('title')->value;
    $variables['article'][$key]['image'] = $newsNode->field_image->entity->url();
    $variables['article'][$key]['path'] = $newsNode->toUrl();
    $variables['article'][$key]['date'] = $articleCreated;
}

// Pager for News Entity Query
//////////////////////////////////////////////////
$nodesNews =  \Drupal\node\Entity\Node::loadMultiple($newsPostings);
$pathNews = base_path();

$pager = $query->extend('Drupal\Core\Database\Query\PagerSelectExtender')->limit(9);
$result = $pager->execute();

 $build['results'] = array(
     '#theme' => 'page__news',
     '#items' => $nodesNews,
     '#path'  => $pathNews,
   );

   $build['pager'] = array(
     '#type' => 'pager'
   );


return $build;

Answer 1

Modify your query to add pager,for the pagination we need to extend the pagerselectextender and add limit in the query.

 $pager = $query->extend('Drupal\Core\Database\Query\PagerSelectExtender')->limit(9);
 $result = $pager->execute();


/////////////////updated////////////////////
     $query->get('node')
     $query->condition('status', 1, '=')
     $query->condition('type', 'article')
     $query->sort('created', 'desc')
     $pager = $query->extend('Drupal\Core\Database\Query\PagerSelectExtender')->limit(1);
     $newsPostings = $pager->execute();
////////////////////updated///////////////////////////


  $build['results'] = array(
      '#theme' => 'page__news',
      '#items' => $nodesNews,
      '#path'  => $pathNews,
    );

    $build['pager'] = array(
      '#type' => 'pager'
    );

Answer 2

Use the render service either via dependency injection or directly from service container.

$pager = array(
      '#type' => 'pager'
    );

$build['results'] = array(
      '#theme' => 'page__news',
      '#items' => $nodesNews,
      '#path'  => $pathNews,
      '#pager' => \Drupal::service('renderer')->render($pager)
    );

Then print {{ pager }} into your twig file.