reCAPTCHA box in subscription process

Hi,

I can’t seem to get reCAPTCHA box into the registration(subscription) process within the website theme. I have connected Mailchimp already.

l am trying to do is the following: I have achieved step 1 and 3. I need help with 2 please.

1. User enters their email address into the ‘stay up to date’ box and presses ‘Subscribe’ (ref to image 1)
2. A new window appears displaying ‘image 2’ = reCAPTCHA box where the user follows the instructions to prevent spambots from adding into my subscribers.
3. User receives a mailchimp ‘Thanks for joining us’ email. (ref to image 3)