Congrats! Definitely do your research on the school, program, and area! Have some stories/experiences prepared and practice speaking out loud.
Leading up to my first interview, I would talk to myself in the car and in the shower to practice answering questions. And then see if you can do mock interviews! I’m always happy to help and do one if you need someone to practice with.
There will probably be a few questions that may throw you off, so it’s okay to take a few seconds after they ask to think about your answer. (I found repeating the question in answer format to start off my answer helped the rest of it flow out lol)
Oh and just remember that they like what they see on paper and they want to see you succeed! Just be yourself and let your personality shine through while answering their questions. You’ll do great! good luck!