FCM to a specific page from outside Flutterflow

Hi, I am trying to replicate the functionality of Push Notification messaging in flutterflow from an external app. I can trigger the FCM msgs with python using the Firestore SDK, but cannot do the following:

Specifically I want to direct users when they click on the notification to a specific page, eg /myBuilding and pass on the page parameter buildingParam = Test

Any help would be appreciated thanks