From your textbook, Biology (eight edition) by Campbell and Reece, you will need to read chapters 1, 2 and 3. This material should be review for you from biology and chemistry classes.
As you read, you should take notes that will be useful to you when studying for your first exam. That exam will be shortly after school begins.
Use the concept checks within each chapter to test your knowledge and check yourself using the answers in appendix A at the back of the book.
Follow the same procedure at the end of each chapter by taking the self-quiz and checking your answers.