I moved your post to the "Linux and Platform" discussion (instead of it's original location, Welcome). Having your post in the right forum may lead to a better result.
Additionally, providing more information may give people the data they need to provide a response. For example:
Is this Red Hat Linux or Red Hat Enterprise Linux? If it's the former, that distro was discontinued in something like 2002 and I think it would be very difficult to get anything modern for it.
What version and update release are you working on? (should be reported in /etc/redhat-release file)
Because drivers are kernel related, what kernel are you running? (a uname -a would contain this information)
How are you trying to install this driver? Is it something you're compiling from source? Is it an additional RPM that you downloaded from RealTek or somewhere else? If so, where might that have been?
Are you getting a specific error message when attempting to do something? If so, what is that error message?