index.js

const characters = ["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","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", "0", "1", "2", "3", "4", "5", "6", "7", "8", "9","~","`","!","@","#","$","%","^","&","*","(",")","_","-","+","=","{","[","}","]",",","|",":",";","<",">",".","?",
"/"];

let passwordsEL = document.querySelectorAll('.passwords')
let lengthEl = document.querySelector('#length-inp')
let numberEl = document.querySelector('#numbers-check')
let symbolEl = document.querySelector('#symbols-check')



function generate(){
    let passLength = lengthEl.value
    let firstPass= createPassword(passLength)
    let secondPass= createPassword(passLength)
    
    passwordsEL[0].textContent = firstPass
    passwordsEL[1].textContent = secondPass
    
}

    

function createPassword(len){
    let password = ''
    
    for(let i=0;i < len;i++){
        //Get a random character from the array
        let character = ''
        
        if ( numberEl.checked && symbolEl.checked ){
            let randomNumber = Math.floor( Math.random() * characters.length )
            character = characters[randomNumber]
        }
        
        else if (numberEl.checked){
            let randomNumber = Math.floor( Math.random() * 52 + 10 )
            character = characters[randomNumber]
        }
        
        else if (symbolEl.checked){
            let arr = characters.slice(0,52);
            arr = arr.concat(characters.slice(52+10))
            let randomNumber = Math.floor( Math.random() * arr.length )
            character = arr[randomNumber]    
        }
        
        else {
            let randomNumber = Math.floor( Math.random() * 52 )
            character = characters[randomNumber]
        }
        
        
        
        //Add it to the password string
        password += character
    }
    
    return password
}

//ClipBoard Copying
passwordsEL.forEach(
    function(el,i){
        el.addEventListener('click',copyToClip)
         
    }
)

function copyToClip(){
    let clip = this.textContent 
    navigator.clipboard.writeText(clip);
    alert('copied')
}