comment

  /**
  * Gets unread comments count for a specific user.
  *
  * @param \Drupal\Core\Entity\EntityInterface $entity
  *   The entity to check comments for.
  * @param int $uid
  *   The user ID to check.
  * @param string|null $field_name
  *   Optional field name to filter comments.
  *
  * @return int
  *   Number of unread comments.
  */
 public 

$new_comments = \Drupal::service('comment.manager')->getCountNewComments($node);

$comment_count = 0;
$comment_fields = $this->commentManager->getFields('node');
foreach ($comment_fields as $field_name => $info) {
 if (!$entity->hasField($field_name)) {
   continue;
 }
 $comment_count += $entity->get($field_name)->comment_count;
}