Overide exisitng project

i have a project with cms that was duplicated for two websites because the contents are same, now one of them is more updated that the other…is there a way to update or override the second website without having to manually copy the content one website one to website two OR having to duplicate the project has that will mean an upgrade of the current plan

Here is my site Read-Only: LINK
(how to share your site Read-Only link)