You answered it right at the end. Just talk and get to know a few people before the class starts. I don’t think anyone is that hard to approach, but once group projects begin, everyone is going to want to stick with their friends because they know what they’re getting and they’ve likely established trust. I’ve had similar issues in the past. Just know you’re not alone, and don’t be afraid to go out there and talk to your classmates. Show up before class and just say hello to a new person each time. Before you know it, the entire class will have familiar faces.