electrical/brakes on 1995 Chevrolet G Series Van (G20)

1. anytime i use the lighter the dash,interior,lights go out
2. its really hard to press the brake down i was told its the brake booster

When you use the lighter does the fuse blow? If so I would suspect a faulty lighter. I can't confirm your brake booster fault with out more information and possibly some hands on testing, but it could defiantly be the cause for your hard brake pedal.
#1 also check the wiring behind the plastic , some times the wiring touches the doghouse and shorts it out