The first navigation exercises that new pilots undergo are prepared with a map, a pencil and a clock. They know which way the wind is blowing from the forecasts and allow for this when they point their aircraft towards the destination.
Like a boat adjusts for the tide a plane does the same with the wind. By comparison a modern navigation system, based on the inertial platforms used on moon missions, give a position accuracy of a few meters after a journey of thousands of miles.
Aircraft store their routes in a data base and with one action the route from say Sydney to Denver will be shown on the flight management display. Turn on the autopilot engage the navigation computer and the plane does the rest.
So… sit back relax and let go of the arm rests. Everything has been taken care of. Leave your fear of flying behind and enjoy being in the care of professionals.