If you are unable to view your Zoom tab or other tabs (Nearpod, Assignments, etc) while in your Course, be sure that the menu bar isn't collapsed. Just click the 3 bars at the upper top-left corner of the page, next to the course name to unhide the menu bar:
If you are having any trouble finding your Zoom tab, don't hesitate to reach out for technical support via email or chat. The following article includes details on how to get in touch with the Tech Team: