Content management system extension link missing

I want to add nested cms pages and their is not any cms link for getting the extension. Is there any other way to add nested cms pages or anyone provide the working link.

Thanku

Hello!
Could you please clarify what you mean by nested CMS pages?
nopCommerce has entity called topic here http://admin-demo.nopcommerce.com/Admin/Topic/List
Did you mean them?

In Topic I want  structure like this:-
Main topic is About and under that subtopics like:-
Product
Categories etc

its not supported as per current topic page structure.

i think you need to customize it as per the category structure and need to create new mapping table etc if you have multiple parent topics