This site was actually very simple to make. I started with by creating a new Google Site. I left everything as default, even the theme "Ski" which is the easiest one to personalize (in my opinion).
I went to More > Edit site layout.
I had already found the background image on the website: Unsplash.com. They have some great free hi-resolution photographs. I chose the one below and downloaded it. I have added it to this page as an attachment.
The icons I used can be found in the freebie section on Noupe.com. They were offered by Freepik.com on June 3, 2013. Here is a preview image of the icon set. You can visit the website to download you own copy of Freepik's 200 Beautiful Flat Icons.
Under the Entire page > Background section I selected None for Color and Wrapper image. I uploaded the background image I selected. Under Options I set Repeat to none and clicked on the checkbox to Stretch to cover.
Under the Site header > Background section I selected None for Color and then I uploaded a semi transparent .png file that I created in Photo Shop (I have added this file to the page as an attachment as well. You can also use the website SumoPaint.com to create similar images if you do not have access to Photo Shop.
I left the Options the default ones. That has the background repeat both horizontally and vertically.
I hope this was helpful. I plan on adding more to these sites and maybe even turning this one into a template.