Alma 45:22

therefore Helaman and his brethren went forth to establish the church again in all the land, yea, in every city throughout all the land which was possessed by the people of Nephi. And it came to pass that they did appoint priests and teachers throughout all the land, over all the churches.

So Helaman and his brothers went out to build up the church again in all the land. They did this in every city in all the land that the people of Nephi had. They chose priests and teachers throughout all the land over all the churches.

So Helaman and his brothers worked to rebuild the church throughout the land—in every city the Nephites held. They appointed priests and teachers for all the congregations.