Your server is online.
The Apache HTTP Server has been installed on this host and is responding to incoming requests on port 80. Until you replace this page or configure a virtual host, every visitor will land here.
Getting started
Replace the file at /var/www/html/index.html (Debian/Ubuntu) or /var/www/html/index.html (RHEL/CentOS) with your own content. After deploying new files, you don't need to restart the server — Apache reads files on every request.
Adding a virtual host
Configuration fragments live in /etc/apache2/sites-available/ (Debian) or /etc/httpd/conf.d/ (RHEL). Activate a new site with a2ensite and reload with systemctl reload apache2.
Logs
Access and error logs are written to /var/log/apache2/ by default. Tail them while you experiment to see what the server is doing.