Often, we call the stages of a star its “life cycle”, and I’ve been thinking about this for a bit.
Stars meet many of the requirements for living organisms: they can consume matter, they can react to stimuli (sort of, does gravity count? e.g. binary systems), they can reproduce (they expel gas clouds on death that can eventually create new stars), they can grow and change size over their lifespan, and they maintain equilibrium (between gravity and radiation pressure from fusion)
What stops stars from being considered living objects?
Specifically, an organism has to store latent information that’s unobservable to anything it interacts with (i.e., its ecosystem)—or at least, anything with an interest in predicting and controlling it. Otherwise, it has no possibility of independent behavior, and it’s effectively part of a colony organism (or an organ of another organism). It also has no differential behavior for natural selection to act on, so it can’t evolve in a Darwinian sense.
To take your example of bacteria, we don’t know and control the entirety of each individual bacterium’s behavior, but it has happened: it’s how mitochondria ceased to be independent organisms.