what did you see on your browser when accessing the index.php?
do you see any errors in your httpd logs?
did you install the php-mysql package?
Is index.php included on your DirectoryIndex on httpd.conf?
You can test if your php is working , by creating a test page e.g.
phpinfo.php, with contents
then browse it http://ipaddress/phpinfo.php
If you are able to view the page, then your web server is configured to display php pages.