[Date in Contact Field is today (any time)] How can I use Custom Object Field instead of Contact field?

Hi all,

I am creating a program that will automate sending of emails at a specific time. Each contact has their own send date. I created a custom object for this. However, I can't find a decision rule where I can check if the Send Date column in my custom object table is today. Is there a way I can use a custom object field? THanks.

Regards,
Fern