The stock ROM of the phone has to be reinstalled. It can only be done via computer system. I'd suggest u take it to a phone repairer, because attempt to do it on ur own might stress u a lot, and u might do it wrong, seeing as you're not used to these things.

What option did u click when u got to that screen?

Physics. Any branch of physics at all

jnfoage:
This was a question a math professor of mine would ask physics students at their Ph.D. oral exam, but it doesn’t really involve any advanced physics. The question: when we look in a mirror, left and right are swapped - that is, our image’s left hand is our right hand, etc. Why aren’t up and down swapped?

Whoever answers this correctly has two points.

Because the mirror reflects images from front to back, not even left to right.

irishprince3@gmail.com I'm very interested.