In 2019 Greece passed a law restricting the right to work for asylum seekers. The asylum seekers have the right to work 6 months after their full registration.
Recognized refugees/persons granted subsidiary protection.
Recognized refugees and persons granted subsidiary protection have the right to work immediately after their decision is issued.
If you are a Ukrainian national and have obtained Temporary Protection status, you can work in Greece. Note that the AMKA (Social Security Number) and AFM (Tax number) are written on the card.
If you have been rejected for the Temporary Protection status, you need to follow the asylum procedures applied for third-country nationals.