Accessing and Using Formula Field

Accessing and Using Formula Field

Hi There,

I created a formula field called 'Day of the Week' in the Leads module that takes the record created time and transforms it into the day of the week. The formula field returns the correct values. 

However, I am unable to find or use the field in workflow rules or in zoho flow. 

How can I automatically copy the value of 'Day of the Week' formula field into a field called 'Day of the Week Display' so I can easily use it across various workflow rules and in Zoho Flow