You hav t go fr cleaning and polishing...to remove calculus and tartar... Practice simple methods at home... Brush twice with colgate total... Mouth wash after every meal... Avoid in bet snacks. Fr yellowness can go fr bleaching after evaluation

Do have any habits like eating paan,tobacco,do u smoke?do u have any cavity in1 or more teeth?

Warm saline rinses are beneficial otherwise but are not going to be a cure to your problem. You need to visit a dentist for a session of teeth cleaning so that the deposits called as calculus can be removed from the teeth because these deposits cannot be removed by toothbrushing alone. Cleaning your tongue with your toothbrush after every time you brush your teeth is also recommended for better oral hygiene. Regards.