Excel macro to set date

Hi I'm not sure if this a correct place to access this but I'm trying to write a macro for an excel spread sheet that will set the date when the week is over.

Here is an example. I wish to change the date when that week is over, there is also 2 more pages at the bottom that have the same spread sheet that will be 2 weeks in advance to it which will also change. I'm not sure how to better explain this though.

Pseudo code would be okay but it does use VB. I tried to post a picture but I can't as I don't have enough rep. Seems like a bad system but okay.

Sub SetDate()
Dim Week1 As Date
Dim Week2 As Date
Dim Week3 As Date

Week1 = "30 / 3 / 2015"
Range("B4").Value = Week1

Week2 = Week1 + "7 / 0 / 0"
Week3 = Week2 + "7 / 0 / 0"

End Sub