Check out example codes for "add item to an array c#". It will help you in understanding the concepts better.

Code Example 1

List<string> ls = new List<string>();
ls.Add("Hello");

Code Example 2

int[] arrayOfNumbers = new int[400];
for (int index = 0; runs < 400; runs++)
{
  	// Using array[index], you can modify the value at that index
    arrayOfNumbers[index] = value;
}

Code Example 3

List<string> l = new List<string>(){"one","two","tree","four",};

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