Use Custom Fields in a Project
Home > selected Project >  menu or right-click >  Settings > Custom Fields
menu or right-click >  Settings > Custom Fields
                                        
Home > Settings drop-down > Project Settings > Custom Fields
Users with the appropriate permissions can use Custom Fields that have been added to a Project when creating and maintaining Metadata Search Fields templates and Metadata View Fields templates
As with other types of Project settings, you can save Custom Fields to a set of templates for use in a new Project. Custom Fields are automatically prefixed with drcustom- and converted to all-lowercase, for example drcustom-mailheaderid . When working with 
If you want to use a Custom Field in a freeform or other search of the imported Project data, surround the field name with single quotes.
Note: Custom Fields and Custom Field templates can be created and managed at both the Project and Organization levels, but are available for use in templates at the Project level only
To add a new Custom Field, use the 
If you have the needed permissions, you can ) and selecting Save to Template.
) and selecting Save to Template.