I have to go to court on june 14th and I am scared....(read more)?

I am a key witness and I am allowed to go into a room to do my say. I am really naive about this whole thing I have no idea what to expect or what I am doing. I have never done anything like this before. What will it be like when I am in that room? Will I be talking live, as in will it be broad casted to the court room full of people as i'm speaking, or will it be recorded first and then played in the court room? Also what will happen when I am in that room, will I be alone? How do I know what to say? I'm so confused.