SQL Server Management Studio (SSMS) is a tool to manage and administer SQL Server and SQL Database.
SSMS is offered free of charge by Microsoft.
SSMS Documentation is available.
When objects are created or modified they are not automatically available for IntelliSense. To make them available to IntelliSense the local cache has to be refreshed.
Within an query editor window either press
Ctrl + Shift + R or select
Edit | IntelliSense | Refresh Local Cache from the menu.
After this all changes since the last refresh will be available to IntelliSense.