How can I input data to excel from inputting data in text box where the text box are from two or more Userform Using Excel VB?

If you declare every textfield that you want to read from public you can do it like this:

 Class MainForm
    Form firstPage
    Form secondPage
    ...

    Private Sub cmdAddData_Click()
     'Copy input values to sheet.
    Dim lRow As Long
    Dim ws As Worksheet
    Set ws = Worksheets("Summary")
    lRow = ws.Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Row
    With ws
        .Cells(lRow, 1).Value = firstPage.txtNo.Value
        .Cells(lRow, 2).Value = firstPage.txtKode.Value
        .Cells(lRow, 3).Value = firstPage.txtNamaPerusahaan.Value
        .Cells(lRow, 4).Value = firstPage.txtSector.Value
        .Cells(lRow, 5).Value = firstPage.txtTime.Value
        'UserForm2Begin'
        .Cells(lRow, 7).Value = secondPage.txtKas.Value
        .Cells(lRow, 8).Value = secondPage.txtInvestasi.Value
        .Cells(lRow, 9).Value = secondPage.txtDanaTerbatas.Value
        .Cells(lRow, 10).Value = secondPage.txtPiutangUsaha.Value
        'UserForm2End'
      End With

    'Clear input controls.
    Me.txtNo.Value = ""
    Me.txtKode.Value = ""
    Me.txtNamaPerusahaan.Value = ""

    firstPage.txtSector.Value = ""
    firstPage.txtTime.Value = ""
    'Userform2Begin'
    secondPage.txtKas.Value = ""
    secondPage.txtInvestasi.Value = ""
    secondPage.txtDanaTerbatas.Value = ""
    secondPage.txtPiutangUsaha.Value = ""

End Sub



End Class

As mentioned if you want to use this approach, you need to set the visibility to public (in the graphical editor its the attribute Modifiers)

The better solution would be you declare an object in the Mainfrom that has attributes for all values you want to have in you Excel file later. Then give this object to every form, for example in the constructor, and fill it. In you Mainform you can then read all attributes form the object and write them to the file. The Object for holding you data would somthing like this:

    Class DataObject
        Public txtNo as String
        Public txtKode as String
        ...
    End Class

You declare it in the first Form that the user can see and then give it to every form that follows

Class FirstForm
   Dim data as DataObject
   ...

   private sub openNextWindow()
       dim sec as SecondForm= new SecondForm(DataObject)
       ...
   end sub
end class

Until you finally are at your cmdAddData where you do it like this:

Private Sub cmdAddData_Click()
     'Copy input values to sheet.
    Dim lRow As Long
    Dim ws As Worksheet
    Set ws = Worksheets("Summary")
    lRow = ws.Cells(Rows.Count, 1).End(xlUp).Offset(1, 0).Row
    With ws
        .Cells(lRow, 1).Value = data.txtNo
        .Cells(lRow, 2).Value = data.txtKode
        ...      
End Sub