1- Role of Backoffice services center team is only Technician?
Plugin auto creates a User Role Technicians, and that is used for job being processed, this feature is evolving and would have more features in coming updates.
2- Cloud Technicians create services or parts or only shop manager role can create services/parts?
No right now only admin can add parts and services, there is no Shop Manager, but in a recent update we will add a Shop Manager which can do the things in plugin other than the Admin. But you would have to wait for that update.
3- Could we rename pickup/delivery to be only delivery
You have to edit plugin files, if you are willing to update that in Print layout , then you can edit the file. plugin >> lib >> includes >> wc_print_functionality.php
4- Could we add fess for each delivery/shipping area or we should add this as additional services/custom field?
There is nothing like this available you have to customize plugin yourself for this.
5- Could we add fields to parts SN/barcode, suppliers, ect.. to parts?
You can use BarCode, to identify parts by its ID or Products by Its SKU