I do not have a stutter, but I think I can help, as I had to make like a ton of appearances before tons of people. My best advice is to simply ignore the audience. Pretend like you are talking to yourself. Thus it will feel like you are just training for your presentation, and you will make yourself forget that you are talking in front of a lot of people. If you happen to be a more extroverted person tho, and the audience is not one of professionals, rather people you know, you can break the fourth wall and start communicating with them, like asking them questions or cracking some jokes. You will be occupied with communication with the audience and will stop worrying, as of my experience. If they start to laugh at smth in your presentation or your stutter, then laugh it off, perhaps joke about it yourself, then if they laughed about your stutter or smth else you cant control, have a serious talk with them after the presentation is over. If you want to make your presentation more interesting and enjoyable for the audience, dm me and ill give some advice, but this is all I can say about how to make it more comfortable for you. Most important thing tho, and this is the edit as i have read your other comments, is to tell the class and the teacher in advance that you stutter. Then they will know why you are nervous or get stuck.