Redhatserver5.4 Permissions

For details about redhatserver5.4 permission-Linux general technology-Linux technology and application information, see the following. Ladies and gentlemen! I encountered a very depressing problem .... It's been a long time ....
In the terminal control of redhat server 5.4, I entered the root directory and wanted to open the file '/etc/httpd/conf/httpd. conf' in the directory, but I was prompted that I had insufficient permissions.
This is the first case: Enter the command '/etc/httpd/conf/httpd. conf' on the terminal to prompt that the permission is insufficient.
Case 2: Use the resource manager to find the httpd. conf file and drag it into the terminal command. When you press enter, the system still prompts that the permission is insufficient.
Case 3: Use the resource manager to locate and click httpd. the conf file is opened, and enter '/etc/httpd/conf/httpd in the terminal command. conf 'is enabled, and the system does not prompt that the permission is insufficient ....
I am very depressed in these three cases. For linux, I am a new starter, but I don't know much about it... Could you help me solve the problem by asking why the root user still has insufficient permissions ??
Thank you! {: 3_125 :}