The file is index.html located in your htdocs directory (where you put your other files.) This file has to be delete/replaced. If it doesn't exist it may be defaulting to the other index.html.en or index.en.html language specific files. In which case they will need to be deleted as well. If you want to "list directory contents" when an index.html file doesn't exist for that directory, you'll need to make a change in your httpd.conf or apache.conf (system dependant) possibly. Some systems have that turned off by default for security reasons.
The config file is usually located at /etc/httpd/conf/httpd.conf on RH systems.