Linguistic Nightmare

Starting tomorrow, my interview season begins, and the problem is—I can't speak English well. Just a below-average guy stuck with Aaaa... uh... Sometimes I stutter, and every time I try to form a sentence, my brain lags like a bad internet connection.

Need advice or some tips before I embarrass myself!

https://preview.redd.it/g9z791iblrge1.jpg?width=500&format=pjpg&auto=webp&s=46c9aea3039e7ade0d6f0455ab28e64a150f7b57