The 'Unsubscribe' tag allows your prospect to opt-out of your automated emails and keep your email campaigns GDPR compliant. Even if a lead unsubscribes, their manual email and call tasks will still be generated.
Create a new template and select the merge tag 'The mandatory opt-out Link' from the list.
Now that you have saved the template, send a 'Test Email' to any user.
On the user end, when the email is received, clicking on the link will unsubscribe the recipient from all emails and updates.