Can someone explain step b step what to do to catch a connecting flight in JFK (JetBlue) ?

Find a Departure monitor (there should be one near the arrival gate). On the monitor find your connecting flight using the time of departure and the flight number. Note the gate number then ask for help with directions to get to that gate (you might need to take a shuttle train but they are well marked). If you checked your luggage it will automatically put on your connecting flight. It's the same procedure to catch any connecting flight at any major airport in the world.