I've done two interviews where they had this type of interviewing. You stand in front of the door you'll be interviewng in for approximately 1-2 mins and read a scenario question or personal question and you just discuss it with your interviewer with the allotted time (5 mins usually) and the move to the next door
The benefits are that you can make multiple first impressions so if you fail at one, you can make it up with another interviewer. The scenario questions are also usually ethical questions so there is no right or wrong answer (as long as you have an answer!)
For preparation: You never know what kind of question they'll ask so try to have some stories from your pharmacy, academic, extracurricular, etc. experiences that could be used as an answer for multiple questions. You may not even get a question that you can even use your experience stories as an answer but it'll get you thinking about why you're going to answer the way you will for a specific question if that makes sense.