There are loads of different types of streaming services, and live TV is just one of them, as is VOD. It can get confusing how the phrase "streaming service" can refer to lots of other things.
VOD stands for Video on Demand, and it's the technical name for platforms like Netflix, Disney Plus, Prime Video and so on. These platforms let you browse through a library of videos and watch at will.
Live TV services mainly let you watch cable channels over the internet, instead of browsing through a list of videos. However there's a lot of crossover, with plenty of live TV services also having small libraries.