I’ve totally been in your shoes, just graduated college. The first interview is always the worst. Mine was terrible but every one gets better (excluding external factors, like if the interviewers are just off putting). After my first interview, I had two others for two separate position and got both positions. I 100% stuttered in all of them. Not as bad as the first. Talking slow helped me and always remember you are in control of yourself. I am a believer in addressing your stutter to them if you feel you need to. Professors and career advisors at my college all suggest it. I did for all 3. I usually wait until I stutter 1-2 times before I say something. Something like “I apologize, I have a stutter and it’s dramatically worse in these types of situations.” I know it’s nothing to apologize for, but it just sounds better. Someone will 100% disagree with me, I’m sure. If the interviews are accepting, they will look past it. If they don’t, you probably won’t want to work for them.