ProctorU is an online proctoring service.
If your instructor is using ProctorU, you will need to access ProctorU via BOLT, create an account (if you don't have one already) and schedule your exams with ProctorU.
Watch for information from your instructor about when to schedule your exams with ProctorU.
You will need a machine with a webcam to take exams proctored by ProctorU.
Please see the attached document ProctorU_Step2_HowitWorksReduced.pdf for instructions on using ProctorU.