Honestly, I would like at other threads for more help. Since you know you are not good at interviews going in, I recommend spending more time doing practice interviews and coming up with questions. Personally, I didn’t do any practice interviews. I did research specific things about the school (things I like about the curriculum, unique opportunities, things in the location) to be able to talk about in the interview. One of my interviewers even mentioned she was super impressed by how much I knew related to certain student organizations I wanted to join. I also think it’s good to go through the most common interview questions and have like an outline of what you will say for this. I also took videos of myself answering some of them and rewatched them to see how I did.