<p>Presently, novel spectrum-sharing techniques are considered a revolution in land mobile services. The expected requirements of future generation are an expansion in capacity, enhancement in data rates, diminution in latency, increased high spectral and energy efficiency, and better Quality of Service. The land mobile system spectrum is limited, not because it doesn’t have enough spectrums available but also due to spectrum estimation and allocation inefficiency. Therefore, new spectrum-sharing techniques should be used to utilize the spectrum efficiently. One such approach involves various spectrum-sharing techniques. This paper proposes an efficient spectrum-sharing Dual Multitier architecture of 5G and beyond Networks, which includes different spectrum-sharing methods ranging from administrative to cognitive and dynamic spectrum sharing. Some of the latest techniques, like Massive multiple inputs, multiple outputs, simultaneous wireless information, power transfer, spectrum harvesting, spectrum relaying, spectrum trading, and leasing, are also incorporated into the architecture for maximum and efficient spectrum sharing. Furthermore, network selection, channel allocation, and other applications (such as license-assisted access, listen before talk, Multitier, and duty cycle), which are useful to cope with the issue of high bandwidth requirement, are also discussed in the paper. This paper describes cognitive radio as a new invention in radio technology that helps in sensing spectrum scenarios and, hence, effectively accesses the vacant spectrum bands and enables it to modify the transmission parameters to share the spectrum supplely. This paper also provides information regarding projects on spectrum sharing by research institutions in different countries. Furthermore, the paper also gives a diagrammatic representation, which gives an idea of the evolution of wireless technology.</p>