Wireless Sensor Networks (WSNs) have been more popular for a wide range of applications due to research ability to monitor and gather data from a variety of situations. However, it remains challenging to achieve Quality of Service (QoS) while maintaining energy efficiency. In the context of QoS optimization for energy-efficient WSNs, this study investigates the crucial issues of localization and deployment concerns. Localization the precise positions of sensor nodes are crucial for effective data fusion and routing algorithms that rely on localization. This study compares and contrasts several localization methods, including range-based and range-free approaches, and explains benefits and drawbacks. The study also investigates the effects on QoS and energy savings of various deployment strategies, including optimizing node location, boosting coverage, and increasing node density. The goal of this research is to find out how to optimize QoS in low-power wireless networks by including latency, throughput, and stability, among other quality of service characteristics, into the design of routing algorithms. Current routing protocols, like Low-Energy Adaptive Clustering Hierarchy (LEACH), are assessed for ability to optimize quality of service while minimizing energy consumption. In addition, this study explores several approaches that might help enhance QoS while reducing energy consumption, such as energy-aware routing, adaptive duty cycling, and data aggregation methods. By thoroughly examining and evaluating localization algorithms, deployment concerns, and routing protocols, this study offers practical and theoretical insights for researchers and practitioners aiming to optimize quality of service in energy-efficient WSNs. Useful and dependable WSN deployments in a wide variety of domains possible with the help of the presented results and suggestions.