Non-Orthogonal Multiple Access (NOMA) functions as a critical multiple-access technology which enables simultaneous user sharing of network resources to boost spectral efficiency. Physical Layer Security (PLS) has become a major security solution for wireless communication protection within 6G networks. Security improvements and decreased latency together with performance enhancement emerge from the integration of NOMA with PLS as a promising solution. The research examines PLS implementation within Cooperative NOMA (C-NOMA) systems regarding different eavesdropping attack types including passive and active threats. An analysis of NOMA system security takes place through evaluations in relay-assisted and Device-to-Device (D2D) communication networks. A Monte Carlo simulation deploys a system which unites a base station along with a relay and two users and one passive eavesdropper. The transmission quality is enhanced through the combination of Amplify-and-Forward (AF) relays with Decode-and-Forward (DF) relays. The system security evaluation depends on four essential performance metrics which include Secrecy Rate (SR) and Secrecy Capacity (SC) in addition to Secrecy Outage Probability (SOP) and Secure Energy Efficiency (SEE). A thorough evaluation technique examines user security improvement strategies alongside their effectiveness in lowering eavesdropping threats. Research will focus on enhancing security optimization by developing enhanced relay strategies and better PLS methodologies.