Hello Rukia,
The exams are now proctored via some online service. Because of that, you will not get the codes directly, you have to schedule a proctored session via the partner portal. Then, after you connect and get in touch with a person that will monitor your exam, that person will paste the code so you can make your attempt. I know Extreme reviews that process (which has been derived from acquired vendor I believe) but that's how it goes right now.
EOS Fundamentals is about EOS based hardware (so ex-Enterasys devices, different CLI and some features), while EXOS Fundamentals is about EXOS (so pure purple boxes). I believe EOS-related classes are obsolete so you should definitely stick to EXOS Fundamentals.
Kind regards,
Tomasz