score:6
We can't know what scares you, but I can say that if you stick to the interstate highway system, those roads have maximum grade of a 6% in mountainous areas, and 4% in general. These are not steep roads.
But from looking on google the only places you are likely to experience mountains are around Knoxville TN. But even then I-75 winds it's way through various valleys.
As for winds, that is more likely to be a weather related aspect that is going depend on when you actually travel. So while it may be sunny and calm now, you could experience a tornado next week (but highly unlikely).
If you have a modern car I recommend using lane assist when driving on the interstates. I've used mine in very windy crosswinds and it really does help in keeping the car on the road.