BAHAMAS
The country with the most letters in its name is the United Kingdom.
There are no countries that start with the letters 'tap.'
The country that has the letters E, A, R, Z, G, and B is Azerbaijan.
Peru is a South American country with a name that is 4 letters long.
Vietnam
America
England
Austria
A desert county with seven letters includes Algeria.
Out of those letters, I'd try America.
BAHAMAS
Denmark.
There is no such country. There is no country that starts with A and ends with T, let alone a 7-lettered one.
Bahrain Belarus BelgiumBermuda Bolivia Britain Burundi
One country that fits your criteria is Finland. It has seven letters, the third letter is 'n,' and the sixth letter is 'a.'
Ecuador England Estonia Finland Liberia Morocco Namibia Tunisia Uruguay