Crowds! is a full fledged crowd system and doesn't come without its own complexity.
Don't fret : this 1min. tutorial will get you started.
The active asset is the top left one. The other thumbnail help you preview what's inside it, and lead to this page.
Once loaded on the scene, the main asset contains everything you need to create the kind of crowd it's made of. In this case, a running one.
Each group inside the "Crowds" one is a different variation on how elements are scattered.
To lighten the weight on the viewport, the crowds are displayed as grey boxes. Get into interactive mode or render to see them.
Build your crowd flow using the existing variations.
Duplicate an existing variation with Edit > Duplicate > Duplicate Node Hierarchies
Place the variations where needed
Hit Render. Voila !