This gist showcases how to construct/create an element from scratch and append it to the dom its further explained in the DOD article by Yasir Gaji

create-elements-1.js

const li = document.createElement('li'); // this creates an "li" element

li.className = 'New-photo'; // this assigns a class to the "li" element

li.setAttribute('title', 'The new kid in town'); // this assigns an attribute to the "li" element

li.appendChild(document.createTextNode('The new list Item')); // this inputs a text node into the newly created "li" element

document.querySelector('ul.showcase').appendChild(li); // THIS WOULD APPEND THIS INTO THE EXISTING ELEMENTS IN THE INTERFACE