In the .blend file there are multiples collections of natural objects such as bushes, leaves, trees and plants. In the render published you can see how some of them where used to create a photorealistic panorama, wich is included in the package.Note: The textures are all packed in the .blend file. If you want the .png file of a texture you have to select an image in the Image Editor and go to Image->Save As...There are textures for the Normal values, the Roughness valus and the Diffuse values for each included 3d model. As you can see from the previews image, there are multiple collection, one for each kind of natural asset.
Some of the particle systems used are hidden when you open the file to improve reactiveness of the viewport, however they are still rendered.
WORKS BETTER IN BLENDER 3.0