To make your site looking 100% same as demo, there are 3 parts:
There are 2 ways to import demo content.
Step 1: Install Advanced Import: One-Click Demo Import plugin. Activate it. I assume you know how to install a WordPress plugin (go to Dashboard > Plugins > Add new > search plugin name then install)
Step 2: Go to Dashboard > Tools > Advanced Import. Upload rome-dummy-data.zip file you get when purchase the theme, then hit “Upload Demo Zip”. Wait few minutes then the demo data (posts, pages, settings, widgets) will be imported.
Step 3: Fix the missing parts of demo content.
Missing featured posts: After importing content, you might see featured posts area is missing. Please read this article to fix it.
Missing Instagram Feed: Please read this article to add Instagram Feed to your site.
Instead of using an all-in-one plugin, you can import each component separately. Some people might not want to import XML content to mix up with existing content. There are 3 parts: