Foxy2 - From my experience, on an SBDU (Single Boiler Dual Use) machine like the Profitec Go, or the ECM Classika, or the Bezzera Unica, or the Lelit Victoria, you’ll always need to do some purging before steaming to create some headspace in the boiler so steam can be produced.
If you don’t want that, consider an HX (Heat Exchanger) or DB (Dual Boiler) machine.