Homework challenge study, Random generated Strings + Numbers Compare

The concept is create a username 1 and a username 2, assign a string value name1, name2 and then unique integers e.g. 01,02 (Respectively.) and then compare the values.

I've written as much code as I understand, This will be coming up in an assignment tomorrow night, so any help would be appreciated. Thankyou.

        public static void main(String[] args) {
        Scanner usernameone = new Scanner(System.in);
        System.out.println("Enter Username");
        String username1 = usernameone.nextLine();

        int usernameNumber1;
        Scanner usernameNumberOne = new Scanner(System.in);
        System.out.println("Enter in your age.");
        usernameNumber1 = usernameNumberOne.nextInt();

        Scanner usernametwo = new Scanner(System.in);
        System.out.println("Enter Username");
        String username2 = usernametwo.nextLine();

        int usernameNumber2;
        Scanner usernameNumberTwo = new Scanner(System.in);
        System.out.println("Enter in your age.");
        usernameNumber2 = usernameNumberTwo.nextInt();

        if (username1 <= 0) { // Generate random string for name.
        }
        if (usernameNumber1 <= 0) { // Generate random int for number.     
        }
        if (username2 <= 0) { // Generate random string for name.
        }
        if (usernameNumber2 <= 0) { // Generate random int for number.     
        }
        if (username1 == username2) {
            System.out.println("Username 1 and 2 are same.");
        }
        if (usernameNumber1 == usernameNumber2) {
            System.out.println("Usernumber 1 and 2 are same.");
        }

I'm stuck on if the user does not input a number into name 1 or name2 or int 01,02. The program is supposed to randomly generate a number for these variables.

//Then I must compare them. 
 //Name 1 == Name 2? 
 //Number 1 == number2? 
 //Name 1 & Number 1 == Name 2 & Number2.