Can a person ride a scooter will no license or tag?

Almost all DOT regulations say that, as far as they are concerned, any motor vehicle with an engine size less than 50cc in capacity, and capable of no more than 30 or 35mph (or 50 or 55kph) is not required to be licensed. Check your local state's DOT requirements, and also your local community laws: there may be differences. Also, be aware that in California, 2-stroke vehicles can no longer be sold, titled or licensed.