Start by creating the Voxel Play Environment game object. This component is responsible for generating and rendering the voxel world around the camera:

Select GameObject -> Voxel Play -> Create Voxel Play Environment:

It will create the Voxel Play Environment game object like shown in the image below:

The Voxel Play Environment game object is just a placeholder for the VoxelPlayEnvironment script which exposes many options for the world generation and rendering. They are covered in the Voxel Play Environment options section.

One of the key fields you need to assign to Voxel Play Environment is the World Definition. A World Definition contains data about how to generate the world, including which biomes you want, the world size, the terrain generator, any detail generator (for example, for placing villages or cave tunnels) and other aspects. Check the World Definition Architecture section for details.