Execute event onload php file - php

Question

This is the code I have right now and I'd like to execute que script (at the bottom) as soon as the page loads instead of onclick the button.
{capture name=path}
{l s='Amanpay payment.' mod='amanpay'}
{/capture}
<h1 class="page-heading">
{l s='Order summary' mod='amanpay'}
</h1>
{assign var='current_step' value='payment'}
{include file="$tpl_dir./order-steps.tpl"}
{if $nbProducts <= 0}
<p class="alert alert-warning">
{l s='Your shopping cart is empty.' mod='amanpay'}
</p>
{else}
<div class="box cheque-box">
<h3 class="page-subheading">
{l s='Amanpay payment.' mod='amanpay'}
</h3>
<p class="cheque-indent">
<strong class="dark">
{l s='You have chosen to pay by Amanpay.' mod='amanpay'}
{l s='Here is a short summary of your order:' mod='amanpay'}
</strong>
</p>
<p>
- {l s='The total amount of your order is' mod='amanpay'}
<span id="amount" class="price">{displayPrice price=$total}</span>
{if $use_taxes == 1}
{l s='(tax incl.)' mod='amanpay'}
{/if}
</p>
<p>
- {l s='Please confirm your order by clicking "I confirm my order."' mod='amanpay'}.
</p>
</div>
<p class="cart_navigation clearfix" id="cart_navigation">
{*
<a
class="button-exclusive btn btn-default"
href="{$link->getPageLink('order', true, NULL, "step=3")|escape:'html':'UTF-8'}">
<i class="icon-chevron-left"></i>{l s='Other payment methods' mod='amanpay'}
</a>
*}
<a class="button btn btn-default button-medium" href="#" onclick="return confirm(event)">
<span>{l s='I confirm my order' mod='amanpay'}
<i class="icon-chevron-right right"></i>
</span>
</a>
{*<div style="float: right;margin-top: -38px;">*}
{$amanpay_widget}
{*</div>*}
</p>
<script type="text/javascript">
function confirm (e)
{
e.preventDefault();
AmnPy.loadModal();
}
</script>
{/if}
As I said, I need the page to trigger the script onload instead of having to click the confirmation button

Answer 1

Perfect! finally... here was the answer:
<script>
$( document ).ready(function() {
AmnPy.loadModal();
});
</script>