Depends on which belt you're referring to. If it's the cam belt you need to check the position of the cam WRT the crank, and also check the cylinder head/valves for damage. Might see enough through the spark plug holes.
Any other belt just replace, check routing and tension and you're done.
it means that your timing belt needs to be changed.
Check the oxygen sensor. My 1995 Grand Cherokee stopped stalling while driving after it was replaced.
Check timing belt
check tension on fan belt(s)
One posibility to check would be the timing belt. If it broke while driving your car will stall and will not start again. If it was the timing belt you may have a more costly repair bill then just the belt.
Check timing/timing belt
Check your power steering fluid or your fan belt could be making noise.
There is no reset. If the alarm goes off while driving and you are buckled in, you need to check the wires going to the seat belt buckle.
seat belt
That depends on the engine and what belt (timing or accessory).
Did you check the drive belt to see if it broke?
Most likely it is a belt on your car. Usually the squeeling is from a loose belt while idling and will also make noises while driving.