Barcelona is a football clubs that fielded a team for their country.
Gambia (or The Gambia) is a country on the coast of West Africa. Yes, it has a football team.
Australia.
I doubt it as club football and country football are two different things.
Russia
England, I presume. If you are talking about American Football, then the answer is obvious - The USA.
The country that the FK Atlantas Football team plays for is Lithuania, and they are based in the Lithuanian port town of Klaipeda. It was first established in 1962.
A football player can only play for a country where he has citizenship. If he play one official match for a national team he has to play for that particulary team rest of his career.
Nigeria
Derby country i think
The Netherlands, Eindhoven
Tunisia.