Users with Manage Role permissions can delete roles from projects.
Note: All history for the role and associated people is lost once the role is deleted. This cannot be undone.
Project > List > [Select project]
Select the Operations tab in a project, select the on the right-hand side of the role and select Delete role.
Project > Gantt
Under the Gantt Settings, is the ability to customize the Project Gantt view to help condense relevant information. Also, filter the roles that are needed for your request.
On the Project Gantt view, ensure the View roles toggle is on then hover over the role to delete and select the icon. Select the Remove Role button in the role modal.