JSFiddle - React, Tailwind, and code Playground

HTML

<form name="myform">
    <table width="210" cellspacing="2" cellpadding="2">
        <tr>
            <td align="center">
                <table width="173" border="0" cellspacing="1" cellpadding="1" height="130">
                    <tr>                             </tr>
                    <tr>
                        <td colspan="3">                  <input type="text" name="display" size="20" class="form-control" />               </td>
                        <td width="53" height="0">
                            <font color="#FFFFFF">
                                <input type="button" name="clear" value="   C   " class="btn btn-danger"
                                       onclick="myform.display.value=''" onmouseover="window.status='Limpar'" onmouseout="window.status=''" />
                            </font>
                        </td>
                    </tr>
                    <tr>
                        <td width="53" height="0">
                            <input type="button" name="seven" value="   7   " class="btn btn-default"
                                   onclick="myform.display.value+='7'" />
                        </td>
                        <td width="53" height="0">
                            <input type="button" name="eight" value="   8   " class="btn btn-default"
                                   onclick="myform.display.value+='8'" />
                        </td>
                        <td width="53" height="0">
                            <input type="button" name="nine" value="   9   " class="btn btn-default"
                                   onclick="myform.display.value+='9'" />
                        </td>
                        <td width="53" height="0">
                            <font color="#FFFFFF">
                                <input type="button" name="divide" value="÷" class="btn btn-default"
                                       onclick="myform.display.value+='/'" />
                           ...

JavaScript

//Desabilita o post com enter  
$(document).ready(function() {
            $('button').keypress(function(e) {
                var code = null;
                code = (e.keyCode ? e.keyCode : e.which);
                return (code == 13) ? false : true;
            });
        });

//Clica no botão de igual
  $(document).ready(function() {
        $('button').keypress(function(e) {
            if (e.keyCode == 13) {
                $('button[name="calculate"]').trigger('click');
                
            }
            return;
        });
    });