Check out example codes for "c sharp how to read a text file". It will help you in understanding the concepts better.
Code Example 1
// To save the text as one string use 'ReadAllText()'
string text = System.IO.File.ReadAllText(@"C:\filepath\file.txt");
// To save each line seperately in an array use 'ReadAllLines()'
string[] lines = System.IO.File.ReadAllLines(@"C:\filepath\file.txt");
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