Visitors travelling to Turkey from many countries will require a visa to enter Turkey. In 2013 the Republic of Turkey Ministry of Foreign Affairs launched the Electronic Visa (e-Visa) Application System. This new system allows visitors travelling to Turkey to obtain their visas online, it is possible to obtain an e-Visa 24/7. Each person needs to make an application; fill in the necessary information concerning their identity, passport and travel dates and then pay the visa fee. The e-visa is only valid for the purpose of travel for tourism or commerce. For other purposes, such as work or study, you need to contact the Turkish Embassy or Consulate.
e-Visas can be obtained from the following link
Please check the Hellenic Republic Ministry of Foreign Affairs to find out if you need a visa to travel to Greece.