why did my battery light randomly come on while driving and cut my controls?

What is your question?

i was pulling in my driveway the other night when felt the steering wheel seize and the battery light come on. i nearly lost control and went into the woods! what caused this and whats the cost to possibly fix it? im scared to drive this car as it is. this and the catalytic converter in the front is out so i havve no cruise control.