As far as I understand, the network will offer special courses to upgrade the skills of the platform workers, but who will create all the necessary courses? And if there are no courses on the platform?

This will be the task of the manager of the call center company.
What do you mean? How will this work?

Well, the recruiting manager selects the necessary criteria for future employees, if these criteria and training courses are not in the platform database, then the manager can create it independently.