The page is available only when the Phing Support plugin is enabled. The plugin is not bundled with IntelliJ IDEA, but it can be installed from the JetBrains plugin repository as described in Managing plugins.
On this page, enable Phing integration in the current project.
Path to Phing executable
In this text box, specify the location of the phing.bat file. Type the path manually or click Browse and choose the file location in the dialog box that opens.