Update README.md

Author: josemoracard

exercises/03-What-is-a-function/README.md

@@ -10,19 +10,19 @@ For example: If we want to get the sum of two numbers, we can declare a function
 
 ```python
 def sum(number1,number2):
-  return number1 + number2
+    return number1 + number2
 ```
 
-After the function is declared we can use it as many times as we want, like this:
+After the function is declared, we can use it as many times as we want, like this:
 
 ```python
 total = sum(2,3)
 total2 = sum(5,10)
 
-print(total) # prints 5 on the console
-print(total2) # prints 15 on the console
+print(total)  # Prints 5 on the console
+print(total2)  # Prints 15 on the console
 ```
 
-# 📝 Instructions
+## 📝 Instructions:
 
-1. Please calculate the sum between **3445324** and **53454423** and assign the result to a variable called `super_duper`
+1. Please calculate the sum between `3445324` and `53454423` and assign the result to a variable called `super_duper`