If your notebook only scrolls vertically, Vertical is likely selected as its scrolling direction.
Change the scrolling direction
- Open the document.
- Tap the More (...) icon in the top-right corner.
- Tap Scrolling Direction.
- Select Horizontal.
You can also access Scrolling Direction from either of these paths:
- Goodnotes menu > Settings > Document Editing
- More (...) > Document Editing > Scrolling Direction