Hello,
I have over 20 years experience in development of which is 14 years for developing elearning systems and courses.
I have reviewed your project description, what I can offer here is to create the informational website as a CMS (Content Management System) where you could add, edit or remove anything from the website your self; this will include all the data you like just like the website you provided the link for,
The second part, I suggest that I'd create an LMS (Learning Management System), where you can provide the exam(s) as you need, students can register, pay, take the exam, and get a digitally created certificate all automatically based on your requested settings, you can have reports about the usage of the exams, students & etc., you could also here mange the exams by adding, removing or editing the exams or questions and you can make changes anytime.
Please let me know if this suitable for you then I can provide you with links suitable for your request, then I'd create a demo for you.
I am awaiting for your reply to discuss in more details.
Best regards,
Submission of 30-9-2014