When you have enabled and configured service settings from the Project Fields policy of the Project Settings page, you can specify a default service for the project before creating the project's work plan.
To specify a default service,
On the project's Project Overview page, click Details.
The Details tab opens.
Under the Service section, click the selector icon for the Service field.
The service list window opens.
Select a service from the list as the default service, for example, Email service.
The default service is specified.