How do I create a pop up with sign up to newsletter and email sent with discount code

[meelsy23]

I am struggling to work out how to create a homepage pop up saying if someone signs up to our newsletter they will receive 10% off their first order. This includes the automated email that would be sent to them with the discount code. 

I have set up a Discount in Shopify but unsure of how I link this to a pop up and automated email.

Thanks in advance!