What is high school chemistry like(sophomore year)?

So i'm taking chemistry this year and I'm reaaalllyyyy nervous because science is my worst subject.Anyways, what can I do to start preparing for the class and all that???? Liiiike what if I memorized the periodic table or whatever? would that help a lott? ahaa sorry I just get really stressed when it comes to school because I'm alll aboutt straight A's. ANY INFORMATION HELPS, thaaankkksss((: