This chapter investigates multiuser hybrid system combining radio frequency and FSO technologies in an AF relay network, considering asymmetric channel fading conditions. The proposed system model accounts for CCIs affecting both relay and destination nodes. Further, it has been considered that on the first hop of the variable gain AF strategy, multiple RF links facilitate information exchange between the users and the relay node, while FSO links handle data transmission between the relay and destination nodes. The analysis assumes Nakagami-m fading for radio frequency channels and double generalized Gamma (D-GG) fading for the wireless optical channel to incorporate the impact of pointing errors. Through in this system model, exact mathematical expressions are derived for the outage probability and average BER. Additionally, the outage characteristics are explored under high signal-to-noise ratio (SNR) conditions to ascertain the coding gain and diversity order afforded by the system. These asymptotic findings inform a power optimization scheme and offering formulas for optimal power transmission at the transmitting nodes. Moreover, an approximate assessment of the ergodic capacity of the overall system is provided, and theoretical findings are substantiated through the Monte Carlo simulations to validate their accuracy.