Add fields from order in email and PDF invoice

On Step 2 user, who booking, fill custom fields such as: Name and Family, email, mobile, note and other.

How add custom fields from reservation in invoice delivered via email to manager?
Now, I see only email.

But the administrator often need to view this data in email.

Need: Add fields from order from step 2 in email and PDF invoice

I mean field as on screenshot.
This field must be added as separate section in letter body and PDF invoice

The manager no need to look for resertvation in base, and manager phone to clients knowing the phone on email...

how i can add fields from reservation process in email and pdf?
i can't undestand why these fileds not include in basic functionality?