In most cases riding a bicycle on the sidewalk is a LOT repeat a LOT more dangerous than riding on the road. That's because riding on the sidewalk exposes the bicyclist to a lot more blind intersections = every single driveway; and often time very poor sight lines not to mention if riding on the sidewalk in a business area a sidewalk bicyclist also has to contend with pedestrians suddenly entering the bicyclist's line of travel as the pedestrian exits buildings. This too is not to mention how dangerous it is for a sidewalk bicyclist to enter a traffic light controlled intersection and that's because the sidewalk bicyclist is out of the line of sight of most driver because of parked vehicles and the simple fact that a motorist is not expecting a bicycle to enter an intersection from the sidewalk. Can you say Right Hook?

Again, learn to ride in a quiet area, then graduate to quiet streets and build up your skills before going into areas with heavier traffic.

Cheers