I am facing this error Your PHP installation appears to be missing the MySQL extension which is required by WordPress

I ran into the same problem just now, when I upgraded to PHP 7.4 & removed the older version.

If you are on Nginx server, you need to update the configuration file

location ~* \.php$ {
      fastcgi_pass  unix:/run/php/php7.4-fpm.sock;

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