Staff roles can't be permanently deleted, but you can deactivate them to hide them from staff role settings on a staff member's profile.
Deactivate or reactivate a staff role
To deactivate or reactivate a staff role:
Open the App Drawer
then click Setup > Staff > Staff Roles.Select a staff role.
Set the Activate Item option to OFF to deactivate, or ON to reactivate.
If deactivating, you will be prompted to select a new role for any staff currently using the role that's about to be deactivated.
Click Save.