Read comment attachment name and file location

I have a view that has comment, comment attachment(as a file). I want to read the file name and it's location. View looks like below:

I am able to read the title by the below code:

 public function execute(ContentEntityInterface $entity = NULL) {
    // publish the selected comment
    $entity->setPublished(TRUE)->save();

    //Read all the fields from entity
    $comment = $entity->get('comment_body')->getValue();
      //dd($comment); //throws comment title correctly
    $attachment = $entity->get('field_attachment')->getFileName();
      //dd($attachment); //errors at getFileName() function
}

I want to get the filename and file path. How to achieve it?