Both the while and for loops do the same thing. I bet you are wondering why we should even bother learning them both. A for loop is great for iterations through arrays and lists. A while loop is great for holding code execution until a condition isn't met.
I don't want you to worry about while loops for now. We will go through more complex examples when you learn about coroutines in Unity. A coroutine is a special type of method in Unity that can run through an infinite loop without crashing. Let's forget it for a few chapters. We will definitely use them in the second half of the book when you build your first game!