You can add and manage the Roles for the Customer Portal Users from the Portal User Management -> Roles.
By clicking on Create Role, you can add a role for the portal users. Insert the Role details and select the Relationship Type to select the relationship associated with the Role.
Enable the entities that you want to enable for the portal users. You can enable the product for Order & Quote entities.
The Relationship selection is provided to select the relationship that is created in CRM between the contact/account and the entity.
If you have authenticated the SharePoint in the PortalXpand, you can manage the Documents sharing rights for the Portal Users of the customer portal.
From here, you can enable “Document Access” and allow to add the Files & Folders to the portal users from the Customer portal. You can enable the ‘Delete’ option if you want to give permission for the delete.
After configuring the Role details, save the details, and the newly added portal user role will be listed under the Roles.
Note: If an admin has enabled the entity for the SharePoint from Dynamics 365, only then it will be listed under the Document section.