Not a stutterer, but the advice I would give is to let them know that you stutter, and then, well, do your best to give a good speech. Good does not mean stutter-free, rather interesting and impactful. If you need advice on how to do that, dm me, i have experience. By letting them know that you stutter, they for one will not take it as you pausing to cheat or whatever, but bc of a speech disorder, and for two will understand why you are nervous and such. It is gonna be ok.