What is a competency-based or behavioral interview?
In summary, this type of interview is one where the interviewer seeks evidence that you have the skills and experience required to do the job. Using your past experience and actions to determine the future.
The interviewer will be asking questions developed around the job and person specifications, so think carefully about examples from your own experience that match or complement these specifications.
Remember that you can use examples from contexts other than work, for example, you may never have worked in a team in the same type of organisation but you have participated in teams elsewhere.
It's important to show an ability or interest in being able to learn new skills; if you are asked about something that is outside your experience, describe a situation where you learned something new and suggest you can do so again.
Here is a video that may help you understand the interview techniques used and get you prepared!