I am a new user to Linux.

I have a laptop loaded with Red Hat 8.0 and would like to install Firefox 3.0 on it. It states that I must have certain levels of various programs (Gnome 2.16) for example in order to do so. I do not know how to update these items such as Gnome. I am a former/current Windows user.

Can anyone give me some assistance or point me to a place to obtain such basic information as how to update various applications of Linux?