How to modify wp_config file for set up subdirectory?

Just change define( 'SUBDOMAIN_INSTALL', true ); to define( 'SUBDOMAIN_INSTALL', false );

More here: https://codex.wordpress.org/Multisite_Network_Administration

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