Answer:
It is recommended that you read your owner's manual for the vehicle that you drive. If you have already placed your vehicle in the care of a trusted mechanic and there is no obvious or clear reason for the trouble light to be lit, then there is a way to turn it off; same with the beeping. Every make and model is different, so without knowing what car you drive, the question is impossible to answer.
If you have lost your owner's manual for your vehicle (also known as the driver's manual), I recommend purchasing another. More often than not you can contact the manufacturer of your vehicle for a replacement manual.