Do you need to setup default server site and can´t find where? Here is a little tutorial.

If you have installed clear Debian Stretch and Nginx Webserver via depository, You have to navigate to /etc/nginx/sites-enabled where you can see basic default config files.

If you need e.g. set SSL connection simply edit 00-default-ssl.conf file where You can see root folder, mostly – root /var/www/html; – and index file parameter – index index.php index.html;.