A landing page can go through multiple iterations. You can use undo and redo functions in Pages to quickly address mistakes.
Just click the "Undo" or "Redo" icons from the page editor.
Alternatively, you can use these keyboard shortcuts:
- Mac - ⌘Z to undo; ⌘Y or ⌘⇧Z to redo
- PC - Ctrl-Z to undo; Ctrl-Y to redo