you can google for "mouse look" script for unity. It's the easiest way to achieve what you want. Then for the movement, you can create an FSM with an initial state which contains
1) a get key down action. Get the key W and send the event FINISHED. then in the next state, which follows after the first state FINISHES:
2) use the "translate" action and a "get key up" action. The translate action should work on the "self" space and have a positive value on the z axis. It should work per second and every frame.
then the get key up action should get W again, and send the event FINISHED and return back to the original state.
Now, with this and your mouse look script you should be able to fly for now. Character controllers are vastly complicated, and generally you would use one FSM to get all the input and then send global events to other FSMs to make them do the actual labor or stop it. Though people can do it however they like. Either way, playmaker can do just about everythin normal scripting can do, but it does not offer many "prefab actions" which let stuff magically happen. It all takes a bit of wicked logic
I hope that helped!
cheers,
kiriri