Due to the effort involved in creating the map, and the expense of paying people to build, the map is not free. It is available for a small fee on Patreon. Due note that the 1.20.1 version is not finished yet. You can get both (the pre-releases of the 1.20.1 map and the full release of the 1.16.5 map) here: https://www.patreon.com/OnMod