try a local parts store some of them read the codes for free and will reset them for you otherwise you have to take it to a garage.
Check the brake light switch on the brake pedal. Might have to replace it.
If there is no light at all in whole dash. first check the fuse second check the headlight control switch.
Your shift linkage may have slipped or become loose. Check your linkage.
check you belt
The cheapest way to find out what is wrong with your car is to check the little things before you start spending money. Check for bad fuses, check your battery if it's dead, check if you have enough oil in your car or even enough gas in your car to start it up, definitely check the spark plugs if their bad since you have a older car, air filter. if your car has nothing wrong with those minor problems then your going to have to go to your nearest auto store and ask them what can go wrong in a Chevy Caprice classic.
check for a spark from you r#1 cylinder and if it is fine then it is fuel related. If it's not fine check your distributor cap for wear
check all brake bulbs a filiment may have shorted out
Check the front end components for the cause
Check the fuse.jr
Check fuses
depending on what engine you have, 4.3 v-6 or 305 v-8 or if your lucky the 350......chevy never ran a crank sensor on an engine that old. If it wont start, check spark, if you have spark, check fuel.
A new 2013 Chevy Caprice is sold for $31402. You can buy a cheaper one when you buy a used car. However, you must check carefully before you buy a used one.