First jobs are tough. But it’ll be fine. I’ve had a lot of jobs as a 40+ year old with a stutter. Only locked up twice in all that time. Once on a PA system training session at a Walmart when I was 17. The second on the bridge of a US Navy DDG when repeating back a conning order. Of course everyones issue/severity is different but I always felt like our minds do more damage to us than these little issues like a stutter.