You can duplicate any of your pages at any time. To do this, go to your main dashboard that displays a list of your pages. Then access the more menu (the three dots) of the page you want to duplicate and select Duplicate Page.
All page variants and integrations that you've added will also be copied. Click Duplicate and the new page will appear in the stream along with all your other pages.
Once the new page has been created it is completely independent of the original and can be edited and modified just like any other landing page.