Looking at this plugin. https://solspace.com/craft/freeform
Need a form to do this, any help would be pic guys.
Fill in form - sends email to nominated email with enquiry
If sign up to newsletter is chosen then the name is added to mailchimp list and opt in email sent
If sign up response is negative form still sends email to us, but the users email is not added to the mailchimp list or is added with a status of unsubscribe.