How to upload a prepared html page on Google sites?

In order to create an html page using Google sites, there are some tools and templates in the Google sites itself; however, I did not find an option for uploading an html page (site) that has been created already (outside of Google sites).

Is there any possibility for this purpose ?

I tested Embed option, but it is not what I want, as the embedded html will cover only a part the screen …

P.S. This html page is not a part of website, but it is a whole of website. (The website is a single html page.)