What does "screenshots" mean for the App Store app product page, artwork or real screenshots?

I am creating the images for my app product page in the App Store.
I see that there are screenshot specifications to follow, that seem to be reasonable. Indeed they have the resolution of the screen of the iOS devices.

I would like to understand what scenarios are possible:
1- artwork images has to be created that have the right size for the devices displaying them on their App Store, and they can also contain an area depicting a device running my app (for example, rotated and surrounded by a nice background and some text)
2- a simple screenshot of the app

Many tutorials show that kind of images of scenario 1.
But the "screenshot" size requirements clearly refer to the device screen size, for a screenshot.

Every response is appreciated.
Thanks

If artwork with a real screenshot is allowed (as it seems from some websites creating this kind of screenshots on behalf of the developer), is it mandatory that the screenshot strictly corresponds to the device? I mean, let's say that I upload an artwork with a nice rotated screenshot inside for the iPad Pro 3rd gen App Store requirement, but the screenshot is from a iPad 8th gen device (depicting the same identical user interface and functionalities), will it be rejected?

What does "screenshots" mean for the App Store app product page, artwork or real screenshots?
 
 
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