No, if properly repaired it is just as safe as new.
Yes, it could may mean the car is not safe to drive, have it checked/repaired by a good garage.
Yes you can it, there is only one way to do it and that is by sand blasting the frame then self primer.
your transmission needs repaired
Depends on the car front wheel drive it a cradle rear wheel drive it a sub frame.
Yes. Go to a body shop that has a frame straightener.
It is not legal to drive a car without a windshield in this state.
Repairs and replacement of the top are normally done with the frame on the car.
No. have exhaust checked/repaired
Yes, it is legal.
no there is no legal age to buy a car there is a legal age to drive though
If your car won't drive over 5 miles an hour, it needs to be repaired.
You should not drive the car until the brakes are repaired.