The back of the phone is completely covered aside from the camera lenses, the 'front' has a raised edge around the perimeter of the screen, and when they open to reveal the 'inside' both of those parts end up in your hand so you don't notice them. So basically a regular phone case that can fold. I've been using one for over a year, dropping it constantly cause I'm a natural butterfingers, and even though the case DID break (see below), it broke before the screen did. The screen has a tiny, almost imperseptible fracture and I'm not even sure when I got it but it hasn't affected a single thing. I should point out that when I got it, the only case available at the Verizon store was pretty mid and I've just been too lazy to get a good case.

In short, just look up some (good) screens and you'll see that it's pretty intuitive. As for the screen strength, I'll admit I had the same worry as you but this is honestly the strongest phone I've probably ever had. 10/10 would recommend if interested

Believe it or not but my zflip 5 is the longest survivor out of my devicez so far

the screen is flexible. that's the point.