How to add customize product functionality in shopify

[mrk_rizwan_136]

I want this functionality in Shopify, Can someone guide me on how to achieve this. https://www.paddletek.com/pages/customize. 

I create on my development store.. https://tripal-a.myshopify.com/pages/customise 

pass: 123

but fail to convert the result div into a static image and pass it to the product template like the demo.