There is an article with the title " The first rule of choosing a desktop Linux distribution: User, know thyself"
"User, know thyself"
Why do you want to learn Linux? For what purpose and to what level?
"When you say "I have only two options. RedHat or Debian." Why do you only have two options? It looks like you are a****g for the purpose of future employment. Suppose, we said Debian and a future, prospective employer used Redhat, or vice versa.
Elsewhere in the Forum you talk about Centos. There is also Fedora which is also close to RPM.
How will you install Centos/Debian? Download it yourself? Do a Netinstall? Buy or borrow a disk?
"User, know thyself"