I am an Amazon associate losing access to native ads, but I can't get Product Advertising API to work...

Amazon's native ads and banners are being mothballed, and I am trying to replace them - as recommended - with the Product Advertising API. I have a working access key and can, for instance, generate working requests in the API Scratchpad (https://webservices.amazon.com/paapi5/scratchpad/index.html).

I'm an old-school web builder, very familiar with HTML and CSS, but with only a passing familiarity with PHP, Javascript, etc. I can adapt and install it, but I can't write it. That is, I am not a programmer.

The requests I generate in Scratchpad do not work on my websites. They generate an error. Obviously, they are not "plug and play" widgets like native ads, etc.

Clearly, there's something very basic I do not know or understand. In plain (not-programmer) language, can someone explain what my next steps should be?

Hire a programmer?

I've reviewed the documentation and, for lack of a better explanation, it's all (well, mostly) Greek to me.

Any help or insights would be greatly appreciated.