How to work with Amazon affiliate ads?

I am confused with a lot of Amazon lingos!
I am not sure which one to add so I just picked up Banner ads on my sidebar as of now. But I wanted to know how can I display ads like “Recommended Products” or at least display a random product. I don’t want to go and select a specific ASIN/product. I just want to display random products or the products that the user normally searches.

Right now, the banner is showing ads like “Shop on” or “Find millions of products”