The primary goals of smart cities are efficiently managing the rapid urbanization process, energy consumption, environmental protection, citizen economic and living standards, and people's capacity to utilize and accept contemporary information and communication technology (ICT). The development, decision-making, implementation, and delivery of final, beneficial services under the smart city idea all depend on ICT. The aim of the research is to explore the development of smart cities in terms of AI, ML, and DRL. The methods discussed are effectively used to create the best plans of action for a variety of intricate problems pertaining to smart cities. A comprehensive review of prior approaches used in the fields of cyber-security, energy-efficient smart grid utilization, intelligent transportation systems (ITSs), effective use of UAVs to ensure optimal communications services that can even go beyond 5G, and smart cities with health care systems that are smart enough is provided in this survey. Ultimately, a number of research problems and potential future avenues where the aforementioned methodologies can flourish are detailed in order to make smart city concept real.