The front is whatever you want it to be.  For example in my engine I always use -Z as the front, and I use right-handed coordinates.  So while modeling I (or someone else) just faces the model in -Z and then when loaded into the engine I orient the object transform to point -Z in whatever direction I want the object to face.

On 12/21/2017 at 1:30 PM, curator785 said:

Thank you 0r0d that make sense I guess I will need to rotate all the models and export to fbx with them all facing the same direction.

Yeah, you just need to know what convention your engine will use, or whatever code will actually be doing the rendering and moving around the objects.  If it's some script that you have control over, then of course each model could have its own facing direction as long as that code knows about it.  But unless you like pain, just stick to the convention of the engine you're using.