NeverBlock PHP - The standard solution, easiest to implement and most commonly used. It will be covered most extensively in this documentation.
NeverBlock API - When an unsupported language is required, the API provides endpoints required to get the advertisements directly. To be used when manual solutions are requried.
NeverBlock Proxy - A cross platform application with the purpose of handling API requests and caching of advertisements. This service runs in the background to provide the user with a more direct endpoint through which to fetch advertisements.
WordPress Plugin - A WordPress plugin developed to easily integrate NeverBlock ad zones into your WordPress site.
For what I can see, both NeverBlock PHP and NeverBlock Proxy are the easiest one to setup and you should try installing any of these (in your server). I'm afraid that I can't assist you further in this regard as it requires its own installation process and it will be better if you refer your concerns about it to the software vendor.
Once you get NeverBlock installed in your server, you have to modify your ad code script per their instructions. Only then you will have the ad codes needed for Chevereto which you only need to copy-paste in the banner section of your dashboard settings.