This code will act upon whatever is in cell A1. Just a note: it is very bad practice to name ranges with something that Excel uses (i.e. "Numbers"). Thus, in this code, the named range is changed to myNum. Adjust the ranges to suit your needs.
Code:
Sub test()
Dim myNum As Range
Dim c As Range
Dim Crit As Range
Set Crit = Range("A1")
Set myNum = Range("B3:E6")
For Each c In myNum
If c.Value = Crit.Value Then
c.ClearContents
Else
End If
Next c
End Sub
After you check this out, you can go to View > Toolbars > Forms, and choose CommandButton, and draw a button on the sheet, when you release the mouse button it will pop up a list of macros to assign, choose this one (or if you change the name, use that new name).