Please explain this boolean code

public boolean  applyGuess(char letter) {
    boolean isHit = mAnswer.index0f(letter) >= 0;
    if (isHit) {
      mHits += letter;
    } else {
      mMisses += letter;
    }

Hello, using boolean as a method is confusing me a bit. As my understanding goes, in order to use boolean in a method, you have to pair it with a return method in the code block. If you look at the code above, it does not have a return method so what exactly does

applyGuess(char letter) store? Without a return, would it not make sense to just declare public void applyGuess(char letter) ?

This is my understanding of how this code works, please do correct me:

public boolean  applyGuess(char letter) \\this is the method
 {
    boolean isHit = mAnswer.index0f(letter) >= 0;    \\declaring a seperate boolean variable
    if (isHit) {                      \\ these four lines are just conditional instructions, they do not 
      mHits += letter;           \\ return anything to applyGuess(char letter)?
    } else {
      mMisses += letter;
    }

For comparison here is a similar boolean method but with a return statement

 public boolean dispense() {
   boolean wasDispensed = false;
     if (!isEmpty()) {
      mPEZCount--;
      wasDispensed = true;
    }

    return wasDispensed;
    }

The code above to me, makes sense because it return the value of "wasDispensed" to "dispense()", which is why it was declared a boolean in the first place. Please explain like I'm five as to what the differences are. Thanks in advance :)