Don't forget interviwers will have already looked at your resume, so if you have reached the interview, they will first try to validate what's in your resume.
When I interview people, I am looking for these answers:
1) Will the candidate fit in the team (personality)
2) How does the candidate respond to stress (I usually ask very difficult questions where I am not looking for the right answer, but really how the candidate reacts)
3) Does the candidate use a good process
4) What are the candidate knowledge in relation to the job
For junior positions, interviewers don't expect superstars. They know they will have to coach the candidate. And again, the have seen your resume, so they already have an idea on where you stand. They just want to confirm what is in your resume and have a feeling on how working with you will be like.
So don't study for interviews. Just rest and be relaxed. Be HONEST in interviews, because it is easy to know when someone is bullsh*ting! It is easier than you think!!!