Choose Insert, and then More Gadgets.
In the Google Sites Editor, find the Insert menu, and open it. You will see a list of components you can embed on your site, like Tables, Images, and Links. Find and select the More Gadgets option. This lets you add editable tools such as the POWr Ecommerce to your page.
Copy and Paste
The Gadget manager will appear. Select Add Gadget by URL. Then add this exact URL into the field. Select Add to finish.
Adjust Height and Width
Now that you’ve added your new, customizable Ecommerce Widget to your Google Sites page, you’ll probably want to adjust the size and shape of the Widget. Using the options in the pop-up, pick a height and width for your plugin. You can decide to create a title, scrollbar or title around your Ecommerce Widget, but we advise against it. You'll have more control while editing right through the plugin itself.
Set up POWr Ecommerce
Go to the live Google Sites website and click the gear icon in the top right corner of your Ecommerce Widget.
In the POWr Editor, click Import Existing Ecommerce, find Ecommerce- and click Copy.