Passing telephone interview at noon

for a chief position(50% administrative duty, 50% clinical duty) with a panel of 7 people from a hospital. It was first time for me to apply administration related position since I don't have real experience in this aspect in US(only some in China) and I didn't have good answers for every questions (100% administration related questions), but I was very honesty and enthusiasm. Surprisely, I received the phone call from them for inviting me to have on site interview in the evening (6 hours after telephone interview).

By the way, this position will give me great experience for my career development.

what should I prepare for this position from now on? Help me please!