How to Query Firestore Collections on App Startup and Store in App State lists?

I'm new to FlutterFlow and have been watching tutorials on YouTube. I have extensive experience with bubble.io, so I'm picking up FlutterFlow quite quickly. However, the tutorials don’t cover everything, and I’m unsure whether FlutterFlow is more limited than I expected or if I’m just missing something.

I’m trying to achieve something very simple: when the app starts, I want to query two Firestore collections and store the data in two App State lists so I can use them throughout my app. However, I’m struggling to find a way to do this in FlutterFlow.

Any guidance would be greatly appreciated!