Conditional formatting using VBA

I must confess that I’m really getting out of my depth here. I am VERY new to VBA and I just have no idea how to solve an issue so any suggestions more than welcome! I have the following syntax;

Private Sub CheckBox1_Click()
If CheckBox1 = True Then
Range("B4:G5") = format this range to fill the cells with light grey
ElseIf CheckBox1 = False Then
Range("B4:G4") = do nothing
End If
End Sub

As you can see, I have created a simple check box that when checked should ‘grey out’ or fill in the range of cells light grey. If unchecked, then it should just leave the information in those cells ‘as is’, which is a combination of user input and formula.