I always get marked down for my comments and I just wanted to see if these comments are acceptable or what I should include/where I should include them.

import java.util.*; //so I can use scanner

public class GuessingGame {
   public static void main(String[] args) {
   
      Random rand = new Random ();
      int max = 100; //sets limit on the random number generator
      Scanner input = new Scanner(System.in);
      int guess;//so I can compare console input to random number
      boolean play = true;
      int totalGames = 0;  
      int totalGuesses = 0; 
      int bestGame = Integer.MAX_VALUE; 
      
      System.out.println("Can you guess the word?");
      System.out.println("I am sure you cannot guess!");
      System.out.println("Go ahead and try!");
      System.out.println();
      
      while (play) { //so game will restart after a win
      
         System.out.println("I'm thinking of a number between 1 and " + max + "...");
         int numberToGuess = rand.nextInt(max) + 1;
         int numberOfTries = 0;
         //so user can continue guessing until correct
         boolean win = false;  
         while (!win) {
         
            System.out.print("Your guess? " + numberToGuess);
            guess = input.nextInt();
            numberOfTries++;
             
            if (guess == numberToGuess) {
               win = true;  
            } else if (guess > numberToGuess) {
               System.out.println("It's lower.");
            } else if (guess < numberToGuess) {
               System.out.println("It's higher.");
            }      
            input.nextLine();
         }
         
         if (numberOfTries == 1) {
            System.out.println("You got it right in " + numberOfTries + " guess!");
         } else {
            System.out.println("You got it right in " + numberOfTries + " guesses!");
         }   
         
            totalGames++;
            totalGuesses+= numberOfTries;
            System.out.print("Do you want to play again? ");
            
            //so user can choose to play another game    
                  
            String answer = input.nextLine();
            char firstLetter = answer.charAt(0);
            if (firstLetter == 'y' || firstLetter == 'Y') {
            play = true;  
            } else {
            play = false;                               
         } 
          
         
         bestGame = Math.min(bestGame, numberOfTries);
         System.out.println();               
      }
      
      System.out.println("Overall results:");
      System.out.println("Total games   = " + totalGames);  
      System.out.println("Total guesses = " +  totalGuesses);
      System.out.printf("Guesses/game  = %.1f \n", totalGuesses/(double)totalGames);
      System.out.println("Best game     = " + bestGame);
   }  
}