fix(guide): simplify directory structure

guide/english/csharp/nested-if-statement/index.md

@@ -0,0 +1,26 @@
+---
+title: Nested If Statement
+---
+
+# Nested If Statement
+
+The Nested If Statement is used when upon creating an if statement you want a secondary point of validation or if statement inside of it.
+
+```
+int Price = 100;
+int Quantity = 20;
+
+if (Price == 100)
+{
+  if (Quantity == 20)
+  {
+    Console.WriteLine("Price of an item is 200, and we have 20 in quantity.");
+  }
+}
+```
+
+Therefore since we've predetermined Price and Quantity the output would be:
+
+```
+Price of an item is 200, and we have 20 in quantity.
+```