A recurrent type of question here is about domestic trips within Amsterdam, intercity day trips, travel to and from Schiphol airport.
You can use the official public transportation planner (www.9292.nl) for all these questions. It is fed with information of all train, tram and local/regional bus companies. More importantly, it is updated on real time so you can check whether some train or light rail is late. I highly recommend it. Download the app and have it with you.
It will give you details on which platforms to board, link for waking directions to the stop and more. You can feed any address and most touristic attractions right off the app.