Hello and congratulations on your interviews! To have gotten this far is quite an accomplishment and you should be proud. The instructors and staff here who will be interviewing you are pretty much amazing! The advice given above has been spot on. I am currently a J1 student with Amnstokes so it wasn't long ago that we were in your position.
Be prepared to talk about why exactly you want to be a nurse, significant challenges you have overcome, tough decisions you have had to make and the process used to make them, and other general questions that will give the interviewers a chance to see who you are as a person and not just a name on an application.
I'm so excited for all of you. Good luck and feel free to ask any further questions no matter how silly you might think they are.
PT was great Amnstokes!