You have a choice of 3 different installation methods
Method 1: Install UpMenu via link
The first and easiest way to install UpMenu is to copy the online ordering link and paste it on your website. UpMenu will then be available to your customers at your-restaurant-name.upmenusite.com (customers will be redirected to this address from your site)
Here you have more information on how to install via link.
Method 2: Install UpMenu on your own domain
The second method of installation is to set up your own domain (you must have purchased it in advance). UpMenu will then be available to your customers at the address in the following format: your-restaurant-name.com
You can combine way 2 (your own domain) with way 1 (paste link) or way 3 (embed on page)
Here you have more information on how to set up your own domain.
Method 3: embed an UpMenu on an existing page (not recommended method)
Here you have more information on how to embed UpMenu into an existing website.