The typical URL expression for Google maps includes references to fields in one of your database fields for the state, city, street. If you replace those references with references to global variables such as $$City, $$Street and $$State, the button in your portal row can be:
Set variable [$$State ; value: PortalTable::State ]
Set variable [$$City ; value: PortalTable::City ]
Set variable [$$Street ; value: PortalTable::Street ]
Or you can use
Set Web Viewer [Object Name: "Web Viewer Object Name Here"; URL: //Google Maps with embedded address field references goes here]
And you'd put your map URL with references to field names in your portal table in place of the text starting with // above.