Thanks for writing in!
We have several demo available for install. You just install a demo content as per your choice then change the content with your original by edit with corner stone. Here you can find list of regular and Expanded demo available for X theme.
https://theme.co/x/ . Just click on demo menu and it will take you to the demo section.
After decide the demo you want to use, lease login to your site and click on the "X" menu in the left. Scroll down to Demo section, choose the demo you want to setup from the drop down and then click on setup demo button. It will import all sample data and setting for your site.
Then go ahead and edit the pages through cornerstone, change the content according to yours.
Hope this is clear to you.