Added the use library instruction to the quick start

Author: sourabhbagrecha

docs/30-quick-start.mdx

@@ -24,4 +24,10 @@ To use work through the exercises, we need to install the official MongoDB GUI:
 
 ![](/img/open-shell-compass.png)
 
+### 5. Switch to the library database in the shell
+
+Once the shell is loaded, execute: `use library` to ensure you are in the correct database.
+
+![](/img/use-library-compass.png)
+
 That's it for the setup, let's get our hands dirty!