Hi @Amber1,
If you are referring to the directions, house rules, and house manual which are included in the confirmation, you would change those under your listing details. The confirmation pulls your "House Manual" from Listing---> Basics; the "House Rules" are pulled from Guest Resources---> "Detailed Description" ---> "House Rules"; and the "Directions" are pulled from Listing---> "Location".
If you are referring to an email that is sent when someone books, I believe you may be referring to the "First Message" that is sent when someone books using "Instant Book". To update that, turn Instant Book on and then you can see where you enter the "First Message" to the guest.
I hope this answers your question @Amber and if so, give it a Thumbs Up!
Cheers
Dave
David
Superhost Ambassador ~ Host Club Community Leader ~ Community Expert ~ Experienced Co-Host