RedHat's last Linux version was 9.0. They decided to only continue their Enterprise version of Linux and discontinued their regular Linux development, leaving that up to the community as the Fedora Project. So "RedHat Linux 10" is actually "Fedora Core 1". The ads up there referring to a "RedHat Linux 10" are just misleading. Such a product does not exist.
Here's the official site of the Fedora Project: