The fast progress of mobile communication technology has resulted in 6G which will be followed by 7G networks. Because of digital transformation, we now need very smart, accessible and eco-friendly communication networks. The review paper discusses 7G wireless networks, listing their main goals, key technologies, new architecture and possible uses. In the paper, the authors focus on quantum communication, terahertz and optical wireless transmission, AI-based control and SAGUNs which are key to the disruptions calling for 7G. The article describes important goals such as live holographic interaction, the Tactile Internet and communication between different planets. Study of this kind also examines the difficulties with spectrum regulation, network security, equipment limitations, making standards and conserving energy. A well-planned schedule highlights the phases needed to advance from the present systems to 7G, including important targets and effects on policies. Secondly, the report considers what is coming in brain-computer interfaces, digital twins and independent communication systems. This paper tries to direct researchers, policy makers and sector players by analyzing recent findings and upcoming trends in 7G communications.