If you see the below image during your pre-exam webcam check, it is because of a privacy setting that is enabled in your camera's software utility. Please be aware that this same image will be all that is displayed to your instructor when they review your video.

Several cameras have privacy settings like this, but the most common is Lenovo. To disable this setting in Lenovo, go to "Lenovo Settings" > "Configure Camera Settings" and toggle the setting from "Private" to "Normal."

Please refer to your manufacturer's user guide for further assistance.