After the info is written down from your notes, hit the spacebar, put the parenthesis then the first word of the source and hit the space bar. Then put the page number and then closing parenthesis. Next, put a period and then the space bar and keep writing the paper.

Example: (Harris 122).

When in high school, you'll be introduced to APA format which is a bit different. It involves the publication date, not the page number. You'll also learn how to write an annotated bibliography. At the middle school level, we use MLA format, which is what you are being taught.