How to create a nameplate extension? [closed]

Your question is not very clear, but I think what you are asking is if there is a WordPress plugin that allows people to customize a product on your website, like the example you linked to? Or, if you could clone that feature by building your own plugin?

So if that is your question, my answer is below:

The type of extension (or plugin) you are looking is a “product customizer” or “product builder“. Simply search for a WordPress plugin using those keywords.

But keep in mind that the website you linked to is not using WordPress, so you might not find the exact same plugin. That website is using Magento, an e-commerce platform.

If you are using WordPress and WooCommerce, you could integrate a product customizer like this one: https://wordpress.org/plugins/zakeke-interactive-product-designer/. I have not tested it myself, but I came across it and thought you might find it useful. There are other plugins that do the same, you just need to be sure you use the right keywords when searching for them.

I hope this answers what I think your question is. If it was not your question, please consider editing your original question to clarify it as it has already been down-voted twice. Otherwise, you might not get an answer.