Open Zotero -- Locate the Zotero application and launch it.  It will open in a separate window.

• Open from your operating system's dock or file manager like any other program.

Zotero Pane: 

• The Pane contains 3 areas - read it Left to Right
• Left:   My Library and your named Collections;   A_Examples ....
• Middle:  Contains the items within the highlighted Collection;  Buddha's brain .....
• Right:  Provides the metadata about the item (Info., Notes, Tags, Related);  Info.:  Item Type:  Book ...