Confirmation message on comment submission

When a comment is submitted, no confirmation message is shown and I would like to achieve this. I want to show the following message.

Your comment has been added for review and approval.

I tried this code.

function mymod_form_alter(&$form, FormStateInterface $form_state, $form_id) {
  else if ($form_id == 'comment_comment_form') {
    $form['actions']['submit']['#value'] = "your comment has been added for review and approval"
  }
}

This only edits the submission button text. Is there a way to add a submission confirmation message?

You would need to add a custom submit handler, and set your message there.

function ahrq_form_alter(&$form, FormStateInterface $form_state, $form_id) {
    else if($form_id == 'comment_comment_form') {
       $form['actions']['submit']['#submit'][] = 'ahrq_comment_form_submit';
    }
}

function ahrq_comment_form_submit(&$form, FormStateInterface $form_state) {
  \Drupal::messenger()->addStatus->($this->t('Your comment has been added for review and approval'));
}