Great question — answering as the UphillTech team:
I was able to add Amazon Affiliated Ads to my Wordpress site via Amazon Auto Links Plugin (free version) and follow the installation instruction. Here is my site as an example. Caveat : I am having a hard time getting it to be placed in my post directly with short code. As soon as you create a "unit by category", you should see some ads in your pages though. Just moving it to the right place it tricky and haven't figured that out yet.
Full answer by il0v3d0g: https://stackoverflow.stackexchange.com/a/65150377 (CC BY-SA 4.0).
Need it done for your business? UphillTech.