JSFiddle - React, Tailwind, and code Playground

HTML

<body>

<header>
	<h1>Exercise 5-2</h1>
</header>


	<p>Item: <input type="text" id="item" size="30">
	<p>Amount: <input type="text" id="amount" size="30">
	<p><span id="message">*</span>
  <p><span id="test">*</span>
	<p><input type="button" id="addbutton" value="Add Item" onClick="processInfo();">

JavaScript

var $ = function(id) {
    return document.getElementById(id);
};

var myTransaction = [];
                              
function processInfo ()
{    
     var myItem = $('item').value;
     var myAmount = parseFloat($('amount').value);
     var myTotal = myItem + ":" + myAmount;
     var myParagraph = $('message');    

     myParagraph.innerHTML = "";
     myTransaction.push(myTotal);
     myParagraph.innerHTML += myTransaction.join("<br>"); 
        
};

(function () {
    $("addbutton").onclick = processInfo;
    
})();