You should know roughly how fast everyday things move. Speed is measured in metres per second (m/s). A person walking moves at about 1.5 m/s, a runner at about 3 m/s and a cyclist at about 6 m/s.
Vehicles are faster. A car on a motorway travels at about 30 m/s, and a passenger aeroplane at about 250 m/s. Wind speeds vary a lot: about 5 m/s in a gentle breeze, and more than 20 m/s in a storm.
Sound is faster still. In air, sound travels at about 340 m/s, which is far faster than any wind or any car. Remember these as estimates, not exact values.