Hi jennifer,
Thank you for contacting the Microsoft Community.
I understand you are trying to take the exam MO-200. Let me provide you details on what can be done on this process.
The URLs you provided are from 3rd party affiliates where we won't have the proper resource to confirm their process. We normally recommend to start by searching for the exam in the Browse Certifications and Exams page then follow the steps in the Register and schedule an exam. From there you can determine the actual price by changing the country where the exam will be taken:

Since the exam is being facilitated by Certiport, we also recommend to reach out to their customer service hotline so they can provide suggestions for you in taking this exam. Please see their contact details by accessing the link below:
Customer service test candidates :: Support :: Certiport (pearsonvue.com)
Kindly let us know should you have further questions.
If this solves your problem, please indicate “Yes” to the question and the thread will automatically be closed and locked. In case we do not receive a response, the thread will be closed and locked after one business day. Please be advised that after the case is locked, we will no longer be able to respond. If the resolution provided did not resolve the issue, please post a new question.
Best regards,