Norway is a Member States of European Free Trade Association (with Iceland, Switzerland and Liechtenstein) and also part to the European Economic Area (EEA). The EFTA is a common market consisting of four European countries that operates in parallel with – and is linked to – the European Union. Therefore as Greece is part of the European Union there are facilities in place to be able to work and operate in Norway for EU members. However this is different if you are not a EU member but hold a resident permit. You will have to apply at the Norway embassy.