My air bag light is always on

Airbags are dangerous items to work on, a lot of online car sites will not entertain questions of repair. They must always be de-energized before working on them, in and of itself not a complicated thing to do. I would advise you to take it to a competent repair place and have them diagnose it. As for the brake light, could be your parking brake foot pedal is dropping a hair now and then, or the fluid in the master cylinder is low, if your car has a cap switch. If your airbag light is flashing, it is giving out a code indicating the area of concern, if not then a scanner can be used to pull the code.