Chamomile, I love when they add things like vanilla or rose to it, or honey flavour! Peppermint is also great, it’s nice and fresh and it’s good for digestion
I usually take fruit forest, because it tastes so well but because we don't have it anymore, I use lemon green tea. That's also very nice to drink it
I always go for a green tea, normally macha but also jasmine or something else. There's so many different kinds of green tea, so choose that instead of black or white tea. It can almost not brew too much, and you can even drink it when it's cold, that's still good.