Update field with selected date, not execution date

Update field with selected date, not execution date

Hello,

I would like to know how to set up a workflow or function to return a selected date from a module and update the respective canvas field with that date. I do not want the date to be the execution date as the selected date can be in the future or in the past. 

Canvas = "Leads"
Leads field to be updated = "Introduction Meeting Date"
Module = "Lead Outreach Tracker"

Thank you!