Blender Market – Creative Bundle v1.2.0: This includes Creative Flow, Random Flow, and Tracklights.
HOW TO INSTALL:
In the viewport, press F4, go to the Preferences menu, and select Add-ons. Click Install on the zip file you downloaded from the retailer. Is it the zip file? Aren't the contents contained within? Then, you can install the add-on. You can type the add-on's name within the search field.
Hotkeys for the Pie menu: Shift+Qfor Random Flow, Ctrl+Shift+X for Creative Flow.
These 3D Blender add-ons were designed explicitly for fast environment hard surface modeling for character and concept art. Still, they are also helpful in various other scenarios, including creating games or movie assets, and could be used as a general modeling aid.