That's tisane/herbal-tea - not "tea" per-se, you can make infusion like this from pretty much anything. Tea has more caffeine than coffee by dry weight. It also depends how long you infuse it, you can easily have a cup of tea that has more caffeine than cup of coffee.

> Depends on the type of tea, for example Roibos tea, ginger, camomile don’t contain caffeine

With "tea" I generally mean _Camelia sinensis_, and the variety of teas made from it (black, green, white, yellow, oolong, puerh, ...)

These are generally known as herbal infusions or tisanes, and not tea.

That varies by locale

I would say that ‘herbal tea’ is a valid term, but that whatever is a ‘herbal tea’ is generally not viewed as ‘a type of tea’, and rather, as ‘a type of herbal infusion’. ‘a type of tea’ is generally viewed as ‘type of tea plant and its dried leaves’.