Correct Subscribe Now on WordPress site (10 to 20 min job)

My WordPress site still points its “Subscribe Now” button to an old GoDaddy mailing setup. Mailchimp is already configured with the correct list; I just need the site updated so that new subscribers are automatically pushed to that list the moment they hit the button—no double-opt-in or manual steps.

Please also enable the standard Mailchimp email notice so I receive an alert each time someone signs up. No visual or functional redesign of the button is necessary; just swap out the backend connection, test it, and show me one successful signup flowing into Mailchimp with the confirmation email landing in my inbox.

I’ll supply WordPress and Mailchimp credentials as soon as we start, and I’m expecting this to be a quick 10-20-minute task for anyone comfortable with the Mailchimp for WordPress plugin, API keys, or similar methods.