Under Settings > Projects section, you will see a set of default fields appear in the blue-shaded box. A blue star denotes a mandatory field.
You can add custom fields of your choice by going to the Custom fields section and then clicking on the ADD CUSTOM FIELD button.
When adding a custom field, you can choose from 7 different field types.
The blue star icon will make the field mandatory.
The blue eye icon will make the field private. Only Administrators, Full Contributors, and other custom permission groups with View Private Fields functionality will be able to view this field.
Some common examples of custom project fields used are Job Number, Phase, Division Code, Project Number, Type of Work, Contract Value, Owner, Units, City, State...
Custom Fields can't be created that start with Phase names + "start" or "end" (ie. "Preconstruction Start" or "Precon Start" as a custom field when the phase is titled "Preconstruction"). This rule is in place to avoid potential confusion caused by duplicate project-related columns under List views.
To learn more about the Settings section click here.