Individual faculty interviews with principal investigators where they ask you questions based on your experience and their own background. They try to match based on which program you want to join. Current students facilitate getting you to and from each interview.
Interview questions [1]
Question 1
Describe undergraduate research challenges and how you overcame them
Submit the application through the system, and waiting for the response. After the interview, you will get the result soon. It would be better if you could get a referral from your friend or classmates.