Im Having an Issue Where My Variable Isn't Storing My Information

My classmate and I have encountered a problem while working on a project. We are making a password generator and we are not allowed to ask the teacher for help but he did say we can use other sources. The goal for the code is to give you random characters based on what you asked.

I've tried to use an array push to push the data to the next function but it just doesn't work when it reaches the part where its supposed to generate the random letters it just generates "undefined" The code is below:

var letters = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z"]

var numbers = ["0","1","2","3","4","5","6","7","8","9"]

var symbols = ["!","@","#","$","%","&"]

var arr = [];

function start(){
println("Welcome to our password generator, with this generator you can create a strong password guaranteed to be acceptible on all sites!")

    var amount = readLine("How many characters should be in your password? ")
    
    password();

}

function password(){
var amountL = readLine("How many letters should be in it? ");

    for(var i = 0; i < amountL;i++){
        var number = Randomizer.nextInt(0,25);
        var rand = println(letters[number]);
        var generatePasswords = rand
        println(generatePasswords)
        arr.push(rand)
    }
    
    var amountN = readLine("How many numbers should be in it? ");
    
    for(var i = 0; i < amountN;i++){
        var number = Randomizer.nextInt(0,10);
        var rando = println(numbers[number]);
        var generatePasswords = println(rando)
        println(generatePasswords)
        arr.push(rando)
    }
    
    var amountS = readLine("How many symbols should be in it? ");
    
    for(var i = 0; i < amountS;i++){
        var number = Randomizer.nextInt(0,6);
        var random = println(symbols[number]);
        var generatePasswords = println(random)
       
        println(generatePasswords)
        arr.push(random)
       
    }
    
    println("you're new password is " + arr );

}