Hi @OnurOnal
First you should find the last friday date to populate that date into cell
The logic i have used here is
1. find the first date of next month
2. do looping by subtracting 1 day from that month until until u get next first friday which would be last friday of current month
use below code and paste in power automate desktop
DateTime.GetCurrentDateTime.Local DateTimeFormat: DateTime.DateTimeFormat.DateOnly CurrentDateTime=> CurrentDateTime
DateTime.Add DateTime: CurrentDateTime TimeToAdd: 1 TimeUnit: DateTime.TimeUnit.Months ResultedDate=> ResultedDate
SET NextMonthDate TO $'''1/%ResultedDate.Month%/%ResultedDate.Year%'''
Text.ConvertTextToDateTime.ToDateTime Text: NextMonthDate DateTime=> TextAsDateTime
SET LFridayFound TO False
LOOP WHILE (LFridayFound) = (False)
DateTime.Add DateTime: TextAsDateTime TimeToAdd: -1 TimeUnit: DateTime.TimeUnit.Days ResultedDate=> TextAsDateTime
IF TextAsDateTime.DayOfWeek = $'''Friday''' THEN
SET LFridayFound TO True
END
END
Text.ConvertDateTimeToText.FromDateTime DateTime: TextAsDateTime StandardFormat: Text.WellKnownDateTimeFormat.ShortDate Result=> FormattedDateTime
Display.ShowMessageDialog.ShowMessage Message: $'''Last Friday Date is %FormattedDateTime%''' Icon: Display.Icon.None Buttons: Display.Buttons.OK DefaultButton: Display.DefaultButton.Button1 IsTopMost: False ButtonPressed=> ButtonPressed
Screenshot of the flow


for demo purposes i am displaying the last friday date by message which in your case is not needed 🙂
Hope it helps !
Mark it as solution if it resolves your query !