What will happen if the black part behind my iPhone screen is scratched when the iPhone is apart?

So I was going to replace my iPhone screen but we realized that we ordered the wrong thing so while my phone was apart I was putting the 6 acres back together that's on the left and right side of the screen and the black part got scratched and when I turn the phone on there's a bunch of colorfully lines and I can't use the phone. Is that scratch the reason the lines are on it like that?

Where is the video from my Icloud, on my phone?

I recently purchased an IPhone 6s, and got the Icloud. I wanted to download a video from the Icloud onto my phone so I could show my sister. The file seemed too large to just play on the Icloud app in my phone, so I saved the video onto my phone thinking that's the only way to view it. Now I can't find it on my phone. Where was it saved to? And how do I find it?

Can't connect to the internet? - 1

Can't connect to the internet from my iphone, my other laptop and even my bro's PC. The only thing that can connect is this laptop I'm using right now with VPN turned on. What's the problem?

Added (1). The VPN on my main laptop has been turned on since this morning. I tried connecting my other devices to a VPN just when I'm having this problem, but no luck at all.

I don't where my phone is?

I have a really old phone and I was going to sell it but I can't find it, I've tried using "find my iPhone" but it's not connected to internet and I've looked everywhere in my room or where I would've put it and I don't where it would be or how to find it, is there another way I could find it?

Buying and IPhone on Ebay?

I need to buy a new iPhone on ebay because mine has broken.

I have the IPhone 6
I'm an AT&T customer

Question: Will any IPhone with AT&T be acceptable to buy?

Question: When I buy the new phone do I simply transfer my sim card from my last IPhone to it or should I take it to AT&T to get my cellular network on it?

Question: What does an "unlocked IPhone" mean?

Can I use another service?

I have an iPhone 6 that is blocked by T-Mobile. The iCloud is clean and it's activation ready. Can I use another service?