Flash a blacklight on the top paper peel (idk how to say this, it’s the paper seal thing that is always satisfying about opening an apple box) on the box before opening it! You should see a faint glowing Apple logo and “iPhone” in text on it. This is by far the only method I know to spot a fake iPhone even before opening the box.

I have no idea. I usually just wait until there’s the red circle thing on the settings app lol