You should have received an email from PeopleCert with your exam voucher. The exam is online. It contains a list of steps you need to take to book your exam. To proctor, the exam PeopleCert uses the software "exam shield". It's a good idea to read how to take the exam on this portal before you start. You can read the guide for Windows here and Mac here.
If you have any questions please contact us at firstname.lastname@example.org