I have a big presentation next week

I have a big presentation next week Im a 15 y/o male in grade 10, me and my buddies were tasked to do a campaign-like presentation, basically they chose me as one of the senators even though they know I have stutter, they claimed they wanted me to face my fears but the truth is I can do basically everything in front of an audience except speaking. My stutter/stammer is the sole reason why I don't recite in class often or talk in front of the class. But the thing is, whenever a teacher asks a question, I immediately get an idea but I stop myself because I'm aware of my stutter, it just doesn't go away even when I try to calm myself or not think about it, or even tryna pray. I can't even talk loud in class. I can pronounce some words but generally words that start with A or T is hard for me. I turned to God but I kept constantly worrying about my future. My buddies' grade relies on ours and my presentation. I need help. Please.