Internet Service Provider such as IVC Telecom

When the customer finds the service they need and chooses the service provider they like, they just order this service by choosing date, time, and where they want to receive the service. Their payment goes to our PSP (Payment Service Provider), When the service provider provides the requested service, the payment is sent to the provider's bank account.

what is the difference between a file server and a internet service provider

yes

Yes, GMail is a e-mail service provider.