He seems to asking Snowden to go back to first principles, to tell the camera about himself as a person. He then follows it up with a series of questions about his family and upbringing.
I've added some bracketing to [hopefully] make things clearer
Q: So [pretend that] I don't know who you are or anything about you.
Snowden: Okay. Um... I work for Booz Allen Hamilton, a defense contractor, I'm sort of on loan to NSA. I don't talk to a Booz Allen
boss, I don't get tasking from Booz Allen, it's all from NSA.
Q: Sorry, I don't [even] know your name [yet]
Snowden: Oh, sorry! I, uh... my name is Edward Snowden.