As this tool is available for students as well as instructors, it has been turned off by default for all courses. As an instructor, if you wish to enable it for your individual course, you will need to go to Customization>>Tool Availability and check mark Record from Webcam for it to appear as a webcam icon in the content editor tools.
More information about it at https://help.blackboard.com/Learn/Instructor/Course_Content/Create_Content/Create_Course_Materials/Add_Social_Media#Browse_My_YouTube_Videos