An operation method of a repeater relaying wireless communications between a base station and at least one terminal in a communication system may include: transmitting, to the base station, a first capability report including information on beam-related capability supported by the repeater; transmitting, to the base station, a first request signal for requesting to perform first configuration for coverage extension of the repeater; receiving, from the base station, information on the first configuration configured based on the first capability report and the first request signal; and relaying the wireless communications between the base station and the at least one terminal based on one or more beams formed based on the received first configuration.