The answer to 'how to test outlet' is to use a basic outlet tester, which is a small, inexpensive device that plugs into the outlet and indicates whether it is wired correctly. This allows you to quickly check if the outlet is functioning properly and identify any potential issues like a missing ground or reversed polarity.
To use an outlet tester, simply plug it into the outlet you want to check. The tester will have a series of lights that indicate the status of the outlet. If all the lights are lit up, the outlet is wired correctly. If one or more lights are not lit, that indicates a problem that may require further investigation or repair by a licensed electrician.