Did you install a boot loader (GRUB or LILO)? If not, you will have to use the boot disk you created during the install process to start up linux. You did create the boot disk, right?
You may want to look over the
RedHat 9 Install Guide that I pointed to in your
previous thread.
Also, be aware that Red Hat 9 is no longer
maintained as of April 30, 2004, so if you want to stay current with bugfixes and security updates, you'd best move on to some other distribution.