Hi Surabhi,
Yes, riding a bicycle is a good sports activity. Riding a bicycle is a efficient exercises to burn calories and at a same time without stressing your joints. Its just that you need to cycle and depending on your cycling speed. More faster you cycle and more inclined the surface is more calories you will burn. It is suggested that if you are cycling on a static cycle then its better to choose interval training which will load you for while and again go back to normal resistance. And make sure that your posture is kept good enough like to keep your back and neck straight so as to avoid any stress on neck and back. Cycling not only burn caklories and help to reduce body fat percentage but it also improves your heat endurance and stamina.
So, if you love cycling then go ahead with it.