Hi Ramana,
Sorry, I left out the bit about column width!
How about:

Public Sub Insert_Col()
Dim Sht As Worksheet
For Each Sht In Worksheets
With Sht.Range("F1")
..EntireColumn.Insert
..Offset(0, -1).ColumnWidth = 12
End With
Next
End Sub

This makes the column width = 12, change according to your needs.
Ken Johnson