Major issues

The main issue is that the brake lights (including the top one) on the passenger side don't work. Changed the bulbs out and still nothing. The airbag light is constantly coming on. Even when driving. The defroster on the passenger side stop working. The heat on the passenger side doesn't work anymore. It blows out cool air. I'm assuming one of the fuses is blown because now the lights where the A/C and heat controls are don't come on anymore. So, at night time I have to turn on the internal lights just to adjust the controls. What is going on? What is causing all these problems?