You can assign internal resources, external resourcesA person or entity that is external to your Salesforce organization. You can use external resources when assigning external staff, such as contractors, to project tasks., or resource roles.
Concept Information
Project Task Gantt (Task Manager)
About Task Dependency Relationships
Related Tasks
Adding a Task Dependency Relationship
Deleting a Task Dependency Relationship
Editing a Task Dependency Relationship
Creating Resource Demands from Project Task Gantt
Associating Project Tasks with Milestones
Reference Materials