Would a regular person like me be able to do this?

Those people are humans just like us, it just happens they were caught doing something illegal and then didn't have millions of dollars to claim it was all a witch hunt and then become president. If you are able to find someone to interview, just remember they are normal people, not anyone special (aside from being poor).

Interesting concept. In no time you will have learned which questions to ask and which not to ask. This could be big.

I dont think you can just walk into a prison like that. You might need some sort of authorization.