Πηγές-Μέσα
Here are some resources to help you complete your task. You can other sites you know of as well.
List of European countries (for the capital and population of the countries)
https://simple.wikipedia.org/wiki/List_of_European_countries
Flags of Europe
https://en.wikipedia.org/wiki/Flags_of_Europe
Map of European countries and interesting facts about them (as well as geographical features)
https://www.kids-world-travel-guide.com/
Monuments in Europe by country
https://en.wikipedia.org/wiki/Category:Monuments_and_memorials_in_Europe_by_country
European traditional dishes
https://gr.pinterest.com/pin/565483296959863954/
Famous people
https://www.imdb.com/list/ls061479461/
Influential european leaders
https://www.cnbc.com/2015/05/07/europes-most-influential-political-leaders.html
Use pictures and /or google map where necessary. Be to the point.
On the last page of the PPT express your opinion about this country (what you liked/not liked). Would you like to visit it?