Display a post via template

get_post() returns a post object. So you can try the following

$post = get_post( 1571 );
setup_postdata( $post );
    the_title();
    the_content();
wp_reset_postdata();

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)