When you're looking at a CMA preview, you can easily navigate through the various tabs or pages using the hamburger menu, the jump to page buttons, or the next page feature.
The hamburger menu is at the top left corner of the CMA preview. Click the menu and then choose the preview page you wish to view.
The jump to page buttons are located at the bottom of the preview window. Click on the button to open the corresponding page in the CMA.
The next page option is found in the bottom right corner of the preview page.