Even if you go to a school without a required public speaking class, you're still going to take classes which require you to speak out loud and give presentations. Nobody likes public speaking classes, even the students who look like they're presenting effortlessly. Speaking is like anything else, do it more and you'll get better at it. I'm not saying this class is going to make you fluent but it will make you more confident with speaking to crowds which WILL make you a better speaker (as we all know, nervousness kills fluency) My advice to you would be to face this class head on, explain the situation to your teacher and do your best. Look at this as an opportunity to ask a professional speaker for advice and learn as much as you can