Best Way to Change a String in a WordPress Post

You can create a new shortcode with this code

add_shortcode("currentDay", function ($attr, $content, $tag) {

    $date = current_time("Y-m-d");

    return $date;

});

and you just have to put [currentDay] in the content

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