<p>Wireless Sensor Networks (WSNs) have become a core component of the Internet of Things (IoT) that facilitate sensing large-scale data and communicating for applications such as smart parking, smart cities, healthcare and smart environmental monitoring systems. Though deployed in harsh environments, these networks are exposed to selfish behaviour of malicious nodes, energy constraints, data leakage and numerous attacks that affect the network lifetime. However, the existing trust-aware and energy-efficient WSN-IoT routing protocols often consider the trust computation, CH selection, and secure routing independently, which results in reduced security, inefficient energy utilization and limited network lifetime. To address these limitations, this paper proposes a novel Energy-aware Trust-aware Bio-inspired Optimized Routing and Clustering (ETBORC) framework that integrates multi-dimensional trust computation, SHO-based CH selection, and CSA-based secure routing into a unified optimization model. The proposed trust computation includes both direct and indirect trust for evaluating of node reliability. To enhance the prolonged network lifetime and increase the scalability, Spotted Hyena Optimization has been employed to select the Cluster Head (CH) by considering trust, residual energy and efficiency in communication. Furthermore, Chameleon Swarm Algorithm (CSA) is used for secure route discovery and dynamically. The proposed ETBORC simulation results in enhancing packet delivery ratio by 7.4%, network lifetime by 14%, throughput by 6.6%, decreasing the energy consumption by 13% and improving the overall Quality of Service (QoS). It mitigates the impact of selfish and compromised nodes, making it highly suitable for the large-scale and dynamic WSN based IoT environments.</p>