The American Institute of Certified Public Accountants (AICPA) administers the Uniform CPA Exam. They develop the exam content, set the standards, and oversee the testing process.

However, although conducted by the AICPA, the exam itself is administered by Prometric, a global testing company.
Prometric handles the scheduling, testing centers, and technical aspects of the exam.

So when you book your exam, you are directed to Prometric’s website where you can book your slot according to the availability at your nearest centres where the CPA exams are administered