How to use WorkDay Function in excel

The Excel WORKDAY function takes a date and returns the nearest working day n days in the future or past. You can use the WORKDAY function to calculate things like ship dates, delivery dates, and completion dates that need to take into account working and non-working days.

Purpose:  Get a date n working days in the future or past.  
Return value:  A serial number representing a particular date in Excel.  
Syntax:  =WORKDAY (start_date, days, [holidays])

Examples:

Basic usage:
In the formula below, WORKDAY is given Friday, January 1, 2021 for start_date, 1 for days, and F5:F13 for holidays. 
The result is Monday, January 4, 2021 since Saturday and Sunday are excluded:
=WORKDAY("1-Jan-2021",1,F5:F13)// returns 4-Jan-2021  
If the start date is moved back one day to Thursday, December 31, 2021, the result is the same, since January 1 is a holiday, and, Saturday and Sunday are also excluded:
=WORKDAY("31-Dec-2020",1,F5:F13) // returns 4-Jan-2021

Worksheet as shown:
In the worksheet shown above, Column B contains a variety of different start dates, column C contains the number of days to move, and “holidays” are the named range F5:F13. The formula in column D (copied down) is:
=WORKDAY(B5,C5,holidays)
At each row, WORKDAY returns the nearest workday in column D, based on the given start date and days to offset.

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