Ho to add get_relative_date and post_except to this get_latest_post query?

You can use human_time_diff( get_the_time( 'U', $post ) ) and get_the_excerpt( $post ) for these two tasks.

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