Awesome @MerinKumar .  Thank you for putting that doc together.  It will help others navigate the GCP integration into Adobe Experience Cloud.

I can see you are attempting to perform an HTTP API update to a profile record.  xdmEntityUpdate is indication you are attempting to perform an upSert.  xdmEntity will use activity to write data upon a dataSet.   Are you attempting to write data upon a profile or experience dataSet?

Hello @MerinKumar    You can use the following as refresh to obtain the GCP refresh token   https://developers.google.com/identity/protocols/oauth2/native-app?hl=en#offline

At this time parquet is only XDM compliant.  You have more flexibility if the data in in json to create a mapping flow.