I need help range selection and cells selection

Ok

I have tested these for you.

The first one gives you the last used cell in column A regardless of the value of i.

The second one returns 1 whatever the value of i

The third one simply returns an error.

Sub Macro1()
'
' Macro1 Macro
i = 20
temp = Range("a" & i).End(xlUp).Row

temp = Cells(Rows.Count, i).End(xlUp).Row

temp = Range(Rows.Count, "a").End(xlUp).Row
End Sub