This example sets variables for the number of columns and rows in the visible range.
Set vr = Spreadsheet1.ActiveSheet.VisibleRange
cc = vr.Columns.Count
rc = vr.Rows.Count
This example makes every other row bold in the current region for cell A1.
For Each rw In Spreadsheet1.Cells(1, 1).CurrentRegion.Rows
If rw.Row Mod 2 = 0 Then rw.Font.Bold = True
Next
This example makes row 2 bold.
Spreadsheet1.Rows(2).Font.Bold = True