Description: Create an email template with an auto populated pdf

I have a custom object named Screenings.
The rep creates the Screening and within the screening they fill out custom fields. There is a custom field on the screening object that asks the rep, do they want to send out an electronic flyer. When the field is equal to Yes, we want to populate 2 custom fields (Screening Location:  xyz & Screening Date: 123) into a marketing electronic flyer as a pdf attachment which will reside within an email template

I want to be able to have this email template (with an auto populated pdf) available to program into a time trigger workflow