how to appendChild inside a function javascript code example

Example 1: how to appendChild in the begin of the div javascript

var element = document.getElementById("div1");
element.insertBefore(para, element.firstChild);

Example 2: add a child html object to another html object in js

//Add child at end of object children list
parent.append(child);
//Add child at start of object children list
parent.insertBefore(child, list.childNodes[0]);