Hi There,
This is our selling page so there no demo that is exactly like this one.
What I would do if I was looking to achieve this would be :
1- Go to WP Admin | X | Load Integrity 1
2-Go to Wp Admin | Theme Options | Stacks | Select Ethos.
3-Go to Wp Admin | X | Install revolution Slider
4- Visit this page and select a slider template which I want to show above masthead.
https://revolution.themepunch.com/free-slider-exchange/
Download it, go to Revolution Slider, Import the Slider Template.
5- Visit The homage page, click edit page, on Wp classic backend editor, scroll down and select the slider as Slider Above Masthead.
6- Go to Theme Options > Header > Select Fixed Header
7- Edit your home page with Cornerstone, give each section a specific ID name , like my-section-1 , my-section-2
8 - Go to Appereance Menus > Create a menu with Custom Links and link them to my sections > #my-section-1 , #my-section-2
9- On Classic backend editor again, turn on One Page Navigation and select the menu you just have created.
I guess that this is a good starting point, if you still have questions, please let us know.