How much different is Amazon vs other platforms like Ebay?

Thinking of launching selling on Amazon, thinking of trying just one product to start.

I have a lot of experience selling on other platforms, but know little of Amazon. I did have a few basic questions though

1) Pictures have to be on a white background (which I do use a lightbox) but can I show the accessories included in the photo or does each item have to have its own photo?

2) I do stuff related to cosplay, are movie titles allowed in products? Example, Back to the Future Marty McFly Halloween Costume Puffer Vest

I know I have read people mentioning getting the “email”

I also plan to just fulfill everything myself. I may move to FBA in the future if volume picked up.