In a method and an apparatus for transmitting and receiving a signal in a wireless communication system, according to one embodiment of the present invention, a PRACH is transmitted through a specific RO from among a plurality of ROs on the basis of a selected SSB, wherein a starting RB index of the specific RO may be determined on the basis of: (i) the lowest RB index of an RB set including the specific RO; (ii) a starting RB index of an RO located at the lowest frequency; and (iii) the lowest RB index of an RB set including the RO located at the lowest frequency.