What's the difference?
Section by Section - Each section is isolated from one another. You will have to use the sidebar to navigate the document.
Fully Scrollable - Your sections become stitched together and you can scroll through your sections seamlessly
How to change the viewing mode
To change the viewing mode, this can only be done at the Template stage, it's not possible to change the viewing mode of an already created document.
When inside the Template editor, click the settings icon in the top right.
When the sidebar appears, you can change the viewing mode to 'Section by Section' or 'Fully Scrollable' and click 'Save and Preview'.
Tip: When editing your template, you may find it's easier to edit in Section by Section so you can clearly see where each section starts and ends.
If you ever find yourself in a situation where the sections aren't linking up with the correct blocks, switching back to Section by Section can make it easier to make these changes and then you can always switch it back again to Fully Scrollable once your structure and order is correct.