Hello @jameszxr,
Accessing GA4 properties/streams is not possible at the moment, as the API is still in beta :
https://developers.google.com/analytics/devguides/config/mgmt/v3
Note: This API does not support GA4 properties. Please join the Analytics Admin API V1 Trusted Testers program to be among the first to test and provide feedback on the new features that include the provisioning and management of GA4 propreties.
For now, you can create new properties with both “GA4” and “UA” tracking codes, which will be visible in the widget.
When you create a property, click on “Show Advanced Options”, then click on “Create a Universal Analytics Property”, then choose to “Create both a Google Analytics 4 and a Universal Analytics property“.
I hope it is clear now.