var textReplacer = new TextReplacer("@");

// template data
textReplacer.AddTag("name","Arash");
textReplacer.AddTag("family", "Mohammadi");
textReplacer.AddTag("age", "25");
             
var inputText = "I'm @name @family, I'm @age.";

string resultText = textReplacer.ReplaceTags(inputText);

Console.WriteLine(resultText);

// output
// I'm Arash Mohammadi, I'm 30

TextReplacer textReplacer = new TextReplacer("@");
textReplacer.AddTag("humanName", "Timmy");

string inputText = "Hello, my name is @humanName, and I love @color.";
string resultText = textReplacer.ReplaceTags(inputText);

// output
// Hello, my name is Timmy, and I love @color.