Could you share a screenshot of your data?
From your description, you may use workbook open event to check if that date is arrives, then input date in to that cell.
This macro checks if today's date matches November 22, 2024. If it does, it sets the value of cell A2 on the sheet1 to today's date.
If you have alredy a target date in one cell, change DateSerial(2024, 11, 22) to Sheets(1).Range("A3").Value
Private Sub Workbook_Open()
Dim targetDate As Date
targetDate = DateSerial(2024, 11, 22)
If Date = targetDate Then
Sheets("Sheet1").Range("A2").Value = Date
End If
End Sub