AutoFill with dynamic destination

You could be stuck on AutoFill, not really required.

Sub Do_It()
    Dim LstRw As Long
    Dim Rng As Range

    LstRw = Cells(Rows.Count, "A").End(xlUp).Row
    Set Rng = Range("C2:C" & LstRw)
    Rng = "=IF(B2>0,1,0)"
End Sub

BTW, if you wanted to do this without the formulas on the sheet:

Sub GrtrThanZero()
    Dim LstRw As Long, c As Range
    Dim Rng As Range, x

    LstRw = Cells(Rows.Count, "A").End(xlUp).Row
    Set Rng = Range("B2:B" & LstRw)
    For Each c In Rng.Cells
        x = IIf(c > 0, 1, 0)
        c.Offset(, 1) = x
    Next c
End Sub