Add the Textures to your Blender project

Open your existing project or start a new one in Blender

Click File -> Append then browse to your downloaded file and click on it once

Click on NodeTree. The texture nodes can be identified by the Burr Elm prefix. Select the textures you would like to use and click Append from Library

The texture nodes will now be available in the Shader Editor from shift + A (or Add -> Group) and find the textures by the Burr Elm prefix.