To create an annotated bibliography using Zotero, you'll first need to add American Psychological Association 7th edition style (annotated bibliography) to your available styles. Open the Cite menu (Mac: Zotero > Settings > Cite, PC: Edit > Preferences > Cite) and click on the link to Get Additional Styles.
This will open Zotero's Style Repository. Search for the style and click on the name to add it to your styles. The next time you open the Cite menu it should appear in the list.
Click on the item and add annotations to the Extra field in the far right pane.
Ctrl+click to select the items you want to use (you may also group them into a collection), then right click and select Create bibliography from items. In the menu that appears:
Click OK, then follow the prompts to save the RTF file to your computer. Next, open the RTF file in Microsoft Word. Alternatively, you can use Copy to Clipboard and paste the text into a Google Doc (Google Docs do not support RTF files), although this may require you to reformat the text. Word and other Microsoft Office applications are available to CU students for free through OIT.