Prepare questions ahead of time and only ask those. Ask the rest some other time. If asked “do you have questions” take a little pause...like previous poster says breathe or count till 5 (not loudly) before speaking
Do you struggle with anxiety? Or anything else? Blurt things because you are nervous? My husband interviews horribly. One time he told me what he was saying at one interview, and I was like what??? Luckily he is hired for his job skills not his interview skills! When he gets comfortable then he does not blurt things as he does well at work but when he meets people the first time, interview etc it’s entirely different story. Granted he has Tourettes and OCD, that’s why I wondered if you have anxiety