Android Question Firebase Notification and notification channel

Sub Process_Globals
    Private fm As FirebaseMessaging
End Sub

Private Sub Receiver_Receive (FirstTime As Boolean, StartingIntent As Intent)
    If FirstTime Then
        fm.Initialize("fm")
    End If
    fm.HandleIntent(StartingIntent)
End Sub

Public Sub SubscribeToTopics
    fm.SubscribeToTopic("general")
End Sub

Sub fm_MessageArrived (Message As RemoteMessage)
    Log("Message arrived")
    Log($"Message data: ${Message.GetData}"$)
    
'    Dim n As Notification
'    n.Initialize2(n.IMPORTANCE_DEFAULT)
'   
'    n.AutoCancel = True
'    n.Icon = "icon_notif"
'    n.SetInfo(Message.GetData.Get("title"), Message.GetData.Get("body"), Main)
'   
'    n.Notify(1)
    
    Private smiley As Bitmap
    smiley = LoadBitmapResize(File.DirAssets, "home.png", 24dip, 24dip, False)
    
    Dim n2 As NB6
    n2.Initialize("default", Application.LabelName, "DEFAULT").AutoCancel(True).SmallIcon(smiley)
    n2.Build(Message.GetData.Get("title"), Message.GetData.Get("body"), "tag1", Main).Notify(1) 'It will be Main (or any other activity) instead of Me if called from a service.
    
    

End Sub

Sub fm_TokenRefresh (Token As String)
    Log("Token : " & Token)
End Sub