Thanks for asking.
Main landing page/Envato Preview: Our landing page is designed using Integrity Stack. We customize the look and feel of the navigation menu as per our requirement. If you would like to mimic the layout, then Integrity 1 stack is a quite close match that can be imported from X > Validation > Demo Content.
- Feature of Main landing page/Envato Preview: Our main landing page is using One page navigation feature, which means that if you click any of the menu item links it will scroll to the relevant section. To implement one page navigation layout, please take a look at following article.
3. Header: You can have header like the landing page using Revolution Slider which can be installed from X > Validation > Extensions. To assign the slider to the header please edit the page in Cornerstone and click on the Settings cog icon and under Page Settings > Slider Settings: Above Masthead > Slider select the slider you have created. Here's a screencast that you can take a look.
To get started with Revolution Slider, please take a look at following article.