You need an autoresponder service for that. If you don’t have one there are plenty of free ones, like MailerLite, and MailChimp (which I don’t really recommend) and there are a lot of plugins if you have a website that will let you create landing pages. With that said, your responder should have a place for you to add a url to a thank you page, or in this case a download page….
The other alternative is collecting the email in the landing page, and sending the gift manually.
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