Fedora made the change to DNF back with Fedora 22, but CentOS and RHEL have stayed with YUM, until now. RHEL has jumped to the next gen package manager, and that's a good thing, but if you're missing YUM or have scripts that rely on it, you'll still have access to the old package manager. What's even better, you don't need to do anything extra.
This is a companion discussion topic for the original entry at https://linuxconfig.org/how-to-install-yum-on-redhat-8