Kombucha is fermented sweet tea (the sugar feeds the bacteria and yeast, and it will eat all of the sugar so the end product is mostly sugar free)
First I would recommend just tasting a bottle of kombucha from a health food store to make sure you like it. its usually around 3.00-4.00$ a bottle (8oz). They have “Earth Fare” and “Whole Foods” grocery stores where I live, plenty of ferments to choose there.
Its a taste that your tongue has never tasted I promise. I bit unusual but very satisfying.
To make it you just pour a recently bought bottle and pour it into a big jar of sweet tea, after a few weeks it forms a “mushroom” that grows and last forever similar to kefir grains…..