Hi Karthi,
You can assign the key to the following macros using customize option available in the Tools Tab.
Snippet Code to activate next sheet of active sheet
Sub Forward()
Dim oDrawDoc As DrawingDocument
Set oDrawDoc = ThisApplication.ActiveDocument
Dim oSheetName As String
oSheetName = oDrawDoc.ActiveSheet.name
Dim oSheet As Sheet
Dim oSheetCount As Double
oSheetCount = oDrawDoc.Sheets.Count
i = 0
For Each oSheet In oDrawDoc.Sheets
i = i + 1
If oSheetName = oSheet.name Then
If i < oSheetCount Then
oDrawDoc.Sheets.Item(i + 1).Activate
Else
MsgBox "Reached Last Sheet"
End If
End If
Next
End Sub
Snippet Code to activate previous sheet
Sub Backward()
Dim oDrawDoc As DrawingDocument
Set oDrawDoc = ThisApplication.ActiveDocument
Dim oSheetName As String
oSheetName = oDrawDoc.ActiveSheet.name
Dim oSheet As Sheet
Dim oSheetCount As Double
oSheetCount = oDrawDoc.Sheets.Count
i = 0
For Each oSheet In oDrawDoc.Sheets
i = i + 1
If oSheetName = oSheet.name Then
If i > 1 Then
oDrawDoc.Sheets.Item(i - 1).Activate
Else
MsgBox "Reached First Sheet"
End If
End If
Next
End Sub