Movement and change your mind/sub moves

A unit has a certain amount of movement they can use, in whatever manner they choose. Beyond charges and compulsory movement, nothing states that all of it must be used.

In your particular example, a normal unit could not do what you are wanting, since you can not combine forward movement with sideways or backwards movement. This wouldn’t apply to fast cavalry or skirmishes, of course.

You do not have to say “this unit will move 2” forward, wheel 1” and then continue 5” forward” and totally commit to that.

Edit for clarity: I meant your example of moving into a wood and then backward. For the fanatic example, if it was not a charge, you could choose to stop dead, or maybe try to wheel around any fanatics that you can fit.