Error 500 is displayed on a website in cases where the server cannot process the site’s PHP code or .htaccess rules due to errors found in them.
By default, errors are written to the logs/ file. You can view them in the Plesk control panel, in the Websites, Domains -> Logs section, or in the file itself via FTP.
If you want to enable the display of errors on site pages, create a .htaccess file in the site folder or open it if it exists and write the following lines:
php_flag display_errors on
php_value error_reporting 7
