Most of the brands of green tea available in the market are ok. Some brands are lemon flavoured, ginger flavoured, that will add taste to the tea.
Brewing; 1. Boil the water >200degrees c 2. If dip tea, dip for 10 minutes, stir and drink it. 3. If powdered leaves put in the boiled water for 10 minutes, filter and drink it. 4. If you are not diabetic add one teaspoon of honey, good for health. Leaves are not sold as green tea leaves in market. If you go yo some tea estate you can get as a friendly gesture.