@Bobotron check /var/logs/apache2/error.log (or for CentOS maybe /var/log/httpd/error_log or error.log) IMMEDIATELY after you try to load the page and "fail."
You may want to edit the connecting-from IP Address from those lines to protect yourself before pasting those lines directly, or better yet just c/p the error code and message.
I really dis-recommend CentOS for anything but a webhost and maybe a tagalong SQL database. It's rigged with defaults for those. Debian-ish platforms are rigged for anything, with an emphasis on free/open source software packages and community-based support. If you're scared of Debian, try Ubuntu. Ubu's a joke clowns don't realize they're telling when they brag about their linux workstation with a GUI, but it makes a neat little server platform.