View a Review record, and click on ⚙️ > Edit Page. Click on the tab set, and add the new tab using the menu on the right. Click on the new tab to activate it. Then, find the Related Record standard component, and drag it into the tab. Then, use the right-hand panel to select Cases. You may need to create some new Actions for creating and editing a case. Once everything is done, Save the changes, then Activate the new Page as the system default, or for each profile you want to use the page on.