toad variables

How do you dynamically get a value into a toad variable.

tying to get somthing like this

c:\folder1\sub_folder\filename’|| to_char(sysdate,‘MM’) || ‘’ || to_char(sysdate,‘DD’) || '’ || to_char(sysdate,‘YYYY’) ||’.csv’ fqfn from dual; result: “c:\folder1\sub_folder\filename_06_27_2017.csv”

I want to use it in email automation.

Try mine solution:
damir-vadas.blogspot.co.at/…/toads-automation-designer-and-sqlplus.html