Show all image size urls for given attachment_id

            $metadata = wp_get_attachment_metadata( $thumbnail_id );
            $base_url = wp_upload_dir()['baseurl'];

            if ( ! empty( $metadata['sizes'] ) ) {
                foreach ( $metadata['sizes'] as $size => $data ) {
                    $url = $base_url . '/' . $data['file'];
                    echo "Size: $size → URL: $url<br>";
                }
            }