$node = \Drupal::entityTypeManager()->getStorage('node')->load($nid);
$view_mode = 'teaser';
$renderable_node = \Drupal::entityTypeManager()->getViewBuilder('node')->view($node, $view_mode);
// This is a really long line. 2This is a really long line. 3This is a really long line. 4This is a really long line. 5This is a really long line. 6This is a really long line. 7This is a really long line. 8This is a really long line. 9This is a really long line. 10This is a really long line. 11This is a really long line.