It's an about 3 person panel Zoom interview. The interviewers ask a set list of questions, and will repeat them as often as you need. Federal interviews are a little different from private sector: the interviewers have to stick to their listed questions, so don't be alarmed if they don't pick up a question you try to get them to ask - they can't. But they're not as wooden as some federal interview horror stories suggest: they'll laugh, give you an encouraging smile. Ask questions you're genuinely curious about - that's where you can build rapport.