If you have been tested on arrival in Greece, you must tell them in the above mentionned forms where you will stay. You have to go there yourself, self-isolate in that hotel, and wait for your test result.
If they found Corona on you, and/ or in case you get ill during your stay, you will be transported to a Corona hotel, for at least 14 days. There they will take care of you, and give you food.
The following article has more info:Greek Destinations with Quarantine Hotels for Covid-19 Case
The Greek Tourism Ministry on Friday released the ministerial decision that reveals the locations of the hotels to be used for Covid-19 isolation purposes once Greece opens to tourists on July 1.
Until now, some 60 hotels throughout Greece have responded to a tender announced by the ministry and expressed interest to operate as quarantine spots for tourists who may contract the coronavirus while on holiday in the country.
The hotels will accommodate mild cases of Covid-19 that do not require hospitalization.
The quarantine hotels will be located in the destinations of the following regions:
Region of Eastern Macedonia and Thrace: Drama, Evros (Alexandroupolis), Thassos and Rodopi
Region of Attica: Aegina and central Athens
Region of North Aegean: Ikaria, Lesvos, Lemnos, Samos and Chios
Region of Western Greece: Etoloakarnania, Ilia and Achaia (Kalavryta)
Region of Western Macedonia: Kastoria, Kozani and Florina
Region of Epirus: Ioannina and Preveza
Region of Thessaly: Karditsa, Magnesia (Volos), Alonissos, Skiathos, Skopelos, Trikala (Meteora)
Region of Ionian Islands: Zakynthos, Corfu, Kefalonia, Ithaki and Lefkada
Region of Central Macedonia: Thessaloniki, Kilkis, Pella (Edessa), Pieria (Katerini) and Halkidiki
Region of Crete: Heraklion and Chania
Region of South Aegean: Andros, Thira (Santorini), Kalymnos, Patmos, Kos, Serifos, Sifnos, Kythnos, Naxos, Paros, Rhodes, Syros and Tinos
Region of Peloponnese: Argolida (Ermioni), Arcadia (Tripoli), Corinth, Laconia (Monemvasia) and Messinia
Region of Central Greece: Evia (Eretria), Skyros, Evritania (Karpenisi), Fthiotida (Lamia) and Fokida (Delphi)
According to the ministerial decision, hotels in the regional units of destinations that have a quarantine hotel will not need to keep rooms free for isolation purposes.
The decision will take effect once its published in the Government Gazette.
According to reports, more hotels are expected to be added to the list by July 1, the date when holidaymakers from abroad will be able to visit Greece through 41 entry points, including 27 airports, seven border areas and seven ports.
Moreover, destinations that in the end do not have quarantine hotels will be covered by neighboring areas (for example, a tourist with a coronavirus case on Symi will be accommodated at the quarantine hotel on Rhodes).
From: https://news.gtp.gr/2020/06/26/greek-de ... -19-cases/