Using this bike is easy. First, adjust the seat height so your feet can touch the ground comfortably. To change gears, use the grip shifter to select the right gear according to the terrain. When you need to stop, gently squeeze the brake levers. Remember, don't shift gears when you're stopped, as it can damage the gearset. For maintenance, regularly check the tire pressure to ensure a smooth ride. Keep the chain clean and lubricated to prevent it from rusting and to make gear - shifting smoother. Also, check the brakes every now and then to make sure they're working properly. If you notice any problems, take it to a professional bike mechanic.