1. A method for operating a terminal in a wireless environment, the method comprising:receiving, from a base station (BS), one or more set of one or more synchronization signal with one or more broadcast signal transmitted via one or more downlink (DL) transmit (Tx) beam;
receiving, from the BS, configuration information indicating a first configured number of at least one set of at least one synchronization signal with at least one broadcast signal transmitted via at least one DL Tx beam mapped to each random access channel (RACH) opportunity, wherein the configuration information further indicates a second configured number of RACH sequences for each DL Tx beam;
determining a RACH opportunity corresponding to a set of a synchronization signal with a broadcast signal transmitted via a DL Tx beam from among the one or more set based on the configuration information; and
transmitting, to the BS, a RACH sequence through the determined RACH opportunity.