Hi amar05

Probably something like this 
Option Explicit
Sub add()
    Dim ws As Worksheet

    For Each ws In ActiveWorkbook.Worksheets
        If Not ws.Name = "Sheet1" And Not ws.Name = "Sheet2" _
                And Not ws.Name = "Sheet3" Then

            'add border
            Cells.Select
            Selection.Borders.LineStyle = xlNone
            Range("A2").Select
            Range(Selection, Selection.End(xlToRight)).Select
            Range(Selection, Selection.End(xlDown)).Select
            With Selection.Borders
                .LineStyle = xlContinuous
                .Weight = xlThin
                .ColorIndex = xlAutomatic
            End With

            'apply conditional formatting

            Range("A3:U3").Select
            Range(Selection, Selection.End(xlDown)).Select
            Selection.FormatConditions.add Type:=xlExpression, Formula1:= _
                    "=MOD(ROW(),2)=0"
            Selection.FormatConditions(Selection.FormatConditions.Count).SetFirstPriority
            With Selection.FormatConditions(1).Interior
                .PatternColorIndex = xlAutomatic
                .ThemeColor = xlThemeColorLight2
                .TintAndShade = 0.799981688894314
            End With
            Selection.FormatConditions(1).StopIfTrue = False
        End If
    Next ws
End Sub