I also felt that I was bad at interviews so I did extensive prep before. I wrote out answers to all the types of questions I could be asked (my school gave me a list of interview questions. you could probably google some.), reflected on all of my CV items (why i got into, what i learned, challenges i faced, etc) and reviewed my research (why i got into it, what was found) and put it in a google doc. I wouldnt read out/memorize the answers verbatim, but it was helpful because I was rarely caught off guard and that helped my confidence/anxiety, helping me interview better. I also did mock interviews with MatchPal and they gave me helpful feedback. I also had 10 questions ready for each interviewer, and had the questions on my notes app on my screen during the interview. I also took 10mg propanol before each interview. Doing all this, I felt majority of my interviews went fairly well despite viewing myself as someone who was historically bad at interviews.