1. Install Xdebug on system.

//First, install xdebug package on system:
sudo yum install php-pecl-xdebug.x86_64

//Or with DNF:
sudo dnf install php-xdebug

2. Open and edit the php.ini file:

//Open and edit the php.ini file:
sudo vim /etc/php.ini

//Add this line zend_extension="/usr/lib64/php/modules/xdebug.so" to the file's end.

3. Restart

//Finally, if your have an Nginx server, we should restart the PHP processor php-fpm:
sudo systemctl restart php-fpm

//Or if you have a Apache server, we should restart the httpd server:
sudo systemctl restart httpd