Published Data - where is the data storage located physically?

Hey *,

I'm searching for the place where the data is stored physically after I published it. I've read the data is stored at a Azure database at the cloud - at which place are the cloud databases located - e.g. Europe / USA?

In case we have a O365 User who publishes the data, is the data stored at the O365 account or also at the Azure Cloud?

Do anyone has found further informations about this topic?

Best regards.