Hello @L61791 ,
If you want the guide immediately accessible after the sign-up, I'd recommend linking to it on the landing page's thank you page. If you're wanting the material sent to the new sign-ups, then I'd recommend linking to it in either a welcome email (new sign-up) or new list-join automation. However the file you're wanting to send them wouldn't be technically embedded in either of these methods, you'd have to upload the files to a cloud drive or your account's library, and then link to them from the URLs provided.
See also:
Understanding Triggers for Automation Paths
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