The Dictionary can be accessed by specifying a key to get the associated value. You can also use the ElementAt() method to get a KeyValuePair from the specified index.

var cities = new Dictionary<string, string>(){
{"UK", "London, Manchester, Birmingham"},
{"USA", "Chicago, New York, Washington"},
{"India", "Mumbai, New Delhi, Pune"}
};

Console.WriteLine(cities["UK"]); //prints value of UK key
Console.WriteLine(cities["USA"]);//prints value of USA key
//Console.WriteLine(cities["France"]); // run-time exception: Key does not exist

//use ContainsKey() to check for an unknown key
if(cities.ContainsKey("France")){
Console.WriteLine(cities["France"]);
}

//use ElementAt() to retrieve key-value pair using index
for (int i = 0; i < cities.Count; i++)
{
Console.WriteLine("Key: {0}, Value: {1}",
cities.ElementAt(i).Key,
cities.ElementAt(i).Value);
}

I hope, this will help you.