No, the capital city is not always the largest city in a country. While in some countries the capital city may be the largest in terms of population and economic activity, there are also many countries where the largest city is different from the capital city.
Quito is the capital city of Ecuador.
That is the capital and largest city in Nepal.
Colombia's capital city is Bogotá.
Managua is the capital city of Nicaragua.
Quito is the capital city of Ecuador.
Manila is the capital of the Philippines.
No country is the capital of Asia. First, Asia is a continent with many countries. Second, a capital is a city, not a country. As Asia is not a country, then it does not have a capital city. The countries in Asia would each have their own capital cities, but there is no one city that is the capital of Asia.
There are no countries in Canberra. It is a city, the capital of Australia.
Cairo is the capital city in Egypt. Canberra is the capital city in Australia. Caracas is the capital city in Venezuela. Copenhagen is the capital city in Denmark.
Vienna is the capital and largest city of Austria.
The four countries in Latin America that begin with a "P" are Panama (capital city: Panama City), Paraguay (capital city: Asunción), Peru (capital city: Lima), and Puerto Rico (a territory of the United States, capital city: San Juan).