The fusion of Internet of Things (IoT) and Wireless Sensor Networks (WSN) has brought about a paradigm shift in the realm of IoT-WSN, enabling seamless real-time monitoring and control of remote systems through efficient data collection and transmission. However, the pressing challenge of limited energy resources in sensors demands ingenious strategies to optimize their longevity and harness their capabilities to the fullest extent. Additionally, guaranteeing secure data transmission is of utmost importance to safeguard sensitive information from potential cyber threats. This research proposes a novel approach to address these critical concerns, introducing a trust-based node behavior estimation method for identifying malicious nodes within the IoT-WSN. This technique enhances data transmission integrity, bolstering the reliability and security of the network. Additionally, an efficient routing scheme is presented that optimizes data transmission to the central station, minimizing delays and maximizing the Packet Delivery Ratio (PDR) to facilitate swift and effective communication. Through comprehensive analysis and evaluation, the effectiveness of the proposed approach is demonstrated using key performance metrics such as Delay and PDR. Furthermore, the Future research in IoT-WSN can explore efficient resource allocation algorithms, advanced data analytics techniques, novel communication protocols, and the potential of emerging technologies such as blockchain and artificial intelligence.