This paper focuses on various electric vehicle charging and discharging technologies in distribution networks, alongside Vehicle-to-grid(V2G) grid technology since there are numerous pros to the V2G application that can be utilized in electric vehicles. This V2G technology offers numerous advantages, including a reduction in fossil fuel use resulting in lower carbon emission, reactive power support, active power regulation, and load balancing via valley filling. Despite these benefits of V2G technology, there are also some drawbacks, including limited potential effects of V2G on the grid, communication overhead between EVs and the grid, and infrastructure changes in the distribution network. Furthermore, an in-depth examination of the methods of indirect controlled charging and discharging in a distribution network (DN), delay charging and discharging, intelligent charging and discharging controlled charging and discharging, and uncontrolled charging is also discussed. Our research paper emphasizes and illustrates how important charging and discharging processes, vehicle aggregation strategies, and their optimization are to the financial benefits of V2G technologies. Moreover, this paper summarizes the difficulties related to V2G technology, the effect of electric vehicles on distributed networks, and critical issues associated with EV integration, including technical, environmental, operational, and economic challenges that require further research to ensure the successful implementation of V2G systems in the future.