At most schools, it’s possible to change your class if it hasn’t started yet. You’d need to first find out if there are spaces available in the section that you want, then sign up for that section, then drop your current section. But before you drop your current section of the class, make sure that you’ve gotten into the section that you want.
You can talk to an advisor on your campus to find out how all this is done there, or else look it up in the college’s catalogue/website.