They will probably stress this to you before you begin the interview, but in case they don't -- one of the things they really check for is that you to ask many clarifying questions.
If you're given a problem, don't start solving it immediately -- instead, ask about what kind of input (integers or strings or something else), ask about limitations on the input (could be people's ages or student numbers), ask if there is a certain way they would like you to handle a specific edge case, and anything else you can think of.
They want to see that you are going to try and fully understand a problem before starting to write a solution.
You're welcome to reach out if you have any specific questions. Good luck!