If Formula Help

I'm trying to return a date based on the presence of a checked box. I have project plan where we have multiple similar simultaneous activities going on. The PM will check a box to indicate the start date of the First one so I can run a report to show this date across multiple similar projects in my portfolio. I created a Sheet Summary field and have this formula:

=IF([First Construction]93 = 1, [Start Date]93, "") the value returned is correct 6/26/22.

This looks at the column "First Construction" where the PM will check the box on whatever row is applicable as the First area to start construction. Based on that checkbox, I want to simply retrieve the task Start Date of that row.

How do I convert this to a column formula so that the checkbox could be anywhere on the sheet and return the value in the Start Date for the row that is checked?

I was playing with using @row, but I am doing something wrong as I get #UNPARSEABLE with the below formula. I'm sure it's a simple error. Thanks for your help! Patti

=IF([First Construction]:[First Construction]@row = 1, [Start Date]:[Start Date]@row, "")