The Internet of Things (IoT) has enabled smooth interactions between various physical devices through interconnected networks, significantly changing various industries. However, the quick spread of IoT devices and their integration into critical sectors present serious cybersecurity issues that require quick and unlimited solutions. The main security issues that Internet of Things (IoT) devices and networks must deal with are the focus of this study, which also reviews current safety approaches and possible directions for future IoT device and network security research. Various security risks might compromise the confidentiality, availability, and integrity of data and services that can affect IoT systems. The widespread connectivity and variety of IoT devices—many of which lack conventional security measures—cause these vulnerabilities. Our research delves into multiple layers of Internet of Things security, covering the application and network layers, as well as the implementation of modern security where we also look into several approaches, including the use of lightweight cryptographic solutions designed for low-power IoT devices, the implementation of blockchain for decentralized security, and the application of intrusion detection systems (IDS) driven by machine learning techniques to effectively identify and overcome threats. Each approach faces challenges that include resource limitations, scalability, and the ability of security protocols to be applied to various IoT platforms and sectors. Moreover, future research will likely focus on improving the current approaches as well as developing reliable and effective safety mechanisms that can adapt to the growing development of the Internet of Things. In an increasingly connected world, our study focuses on the significance of these security approaches and the evolution of new defense technologies against cyberattacks.