where to paste the code?

I am using this plugin and have it as a widget on my sidebar. Where do you paste the code? It says paste to web page, but I have it in my sidebar so I don’t know where to paste the code.

All I’m getting is that it is not active, even though it has been activated. Thanks for the help. My page is: kitchenmancooks.com

https://wordpress.org/plugins/feedburner-email-subscription/