Geofx Add-On: Geometry Node Systems
To install GeoFX Simply download the zip file contained in your purchase and install it within Blender user preferences. Then the UI should show up on your right tab within Blender. This video covers how to install Add-ons within Blender: https://youtu.be/4ma-f_9k1FI?si=I-28ycKR8hnbwA1y