The tooth has two anatomical zone, the crown and the root. The crown is the top part that's exposed and visible above the goo( gingiva). It's covered with enamel, which protects the underpinning dentine. The root of a tooth descends below the goo line anchoring the tooth in the mouth.
Brush your teeth at least twice a day for two minutes each time
Use mouthwash to remove food particles left after brushing and flossing
Eat a healthy diet and limit sugary food and drinks