Move wordpress files to sub-folder

Your link does not work, but I think it relates to this:

In wp-config.php add these lines before ‘Happy Bloggin’ text

define('WP_HOME','http://example.com');
define('WP_SITEURL','http://example.com');

The documentation here

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