Ariyo,
The Prepcast Exam Simulator is extremely similar to the PMI PMP exam. When preparing for the PMP exam in 2019, I found that the Simulator was consistently more difficult than the real exam, thereby preparing you well for the real exam, and that observation has been reported frequently on this forum. The wording of the questions on the simulator well-represent the wording on the PMI exam, thereby making it a very useful tool in preparation as it will get you ready for the vocabulary and phrasing of the real exam.
I hope that helps.
Harry
