Internet traffic management is handled by a single central distribution center if that's what is claimed. Is the answer "yes" or "no" in this situation?

Transmission Control Protocol/Internet Protocol (TCP/IP) is a suite of protocols that controls the way information travels from location to location across a network or the Internet. The protocols perform a wide array of functions. From the perspective of penetration testing, why is it important to understand TCP/IP and the layers of the Open Systems Interconnection (OSI) model?

Is it correct to suggest that internet traffic is governed by a single central distribution hub? No matter if the response is "yes" or "no,"

Does the OSI model conform to the TCP/IP protocols, or vice versa? Is there another model that works better in a corporate environment? In other environments? Explain your answers in detail and provide examples to support your perspective.