How do I reorder the field types for the overview of an issue?

[N Grant]

Hoping someone can help me. I am brand new to this.

How do I modify this script to copy the Issue Type into the Summary field.

<script type="text/javascript">
if (document.getElementById("summary").value == "") {
document.getElementById("summary").value = "<Default Value for Summary>\n";}
</script>

We do not have any add-ons to do this. I want to do it using javascript in the field description. It works when I enter text, but I don't know how to call the Issue type.

Thank you in advance for your help.