Questions about Fiber 100 & 1000.

I'm currently Internet 50 & U-verse TV 300 customer (I recently signed up). I didn't know but I am eligible for AT&T Fiber at my address.

1.- Can I upgrade to 1000 without extra charges?

2.- If I upgrade to Fiber 1000, are they going to run real fiber to my home? I mean, I am not a tech savvy but I think the coaxial does not provides 1000 mbps. Are they going to run the fiber in my home or are using any other kind of wires?