Around 3-4 weeks after submitting the online application, they email you either saying you got the interview or not. If you did, there'll also be a link to the open time slots which you can choose from for the specified date.
In the interview, the interviewer first asks you to walk through your CV then asks followup questions and after these goes to the behavioural questions part. These should be in past tense since they're looking for experiences not made up ideas. After 2-3 of these the interview is finished by your questions. I think you should definitely ask 1 or 2 to look interested. Mine was 40 minutes.