calculate a date X number of days before/after given date

[Samantha]

Hello!

I need to calculate set amount of days before a given date, and then set
amount of days after a given date so users can input account information in
correct time frame. Eg, always 21 days before project date or always 10 days
after project end date = Project Lead up time & follow up time

I believe I need to use something akin to the WORKDAY calculation but
company always has a 7 day week and I do not know how to "include any and all
days" in the calculation - 24/7 365

I am a very "newbie" Excel user! Is there something I can use "easily"?
Any assistance is truly appreciated I did look through the postings, and
also in google but it all went a bit over my head. :0)

 

[T. Valko]

"include any and all days" in the calculation - 24/7 365

In that case it's just simple subtraction and addition.

A1 = Project date

21 days before:

=A1-21

10 days after:

=A1+10