Separate bedroom internet

Our main modem/router is in the office area and my son wants to put his computer in his room which is at the opposite side of the house from the modem/router. He has a coaxial cable outlet but wants to know if he can just use a MoCa to tap into the Ethernet or if he has to have another modem/router to be installed in his room. My other two sons are asking the same so any info would be greatly appreciated