Black tea is the most common tea to brew correctly and is often enjoyed by non-tea drinkers. Due to its heavy oxidation, it can handle a higher water temperature and with its big flavours, it can easily be enjoyed with a dash of milk and honey. You can read more about black tea here.
The 3 Essentials - when warm brewing black tea
Black tea can handle to be brewed in 100c° but preferably just below boiling point 97c° is to recommend. Some black teas can only be brewed just above 80 c° and this is due to how far they have gone in the oxidation process. Most of the black tea blends on the market can be brewed with boiling water 97-100c°.
Amount of tea leaves to water
Black tea leaves require approx. 2 - 3g of tea per 300ml of water, which is around about 2-3 teaspoons of tea. This can vary a bit due to how much other ingredients your tea blend is filled with. You can always choose if you want a weaker or stronger cup of tea by adding a bit less or more tea leaves to your brew.
The Brewing Time
Black teas shall brew between 3-5 minutes generally speaking, for small-leafed teas 2-3 minutes and for large-leafed teas 3-5 minutes. Separate the leaves after a correct number of minutes. If you brew it too long you will have a very strong estranged black tea and if you brew it too short you might find it too weak.
Make sure to always check on the package of your tea that you are about to brew, what the requirements are.