Hello,
I don’t see 2 sliders on the home page. I see just one slider with thumbnails. To get this slider you can import the default Revolution slider example, for example this one https://revolution.themepunch.com/wordpress-slideshow-gallery/
Default Rev Slider archives you can find here https://www.8theme.com/download-plugins/
To get the header like on your site you need to enable header overlap option in header settings and also set the background color for the header.
Regards