I'm pretty sure it would be something like even if a star was coming and we saw it what the fuck could we even do it would just create mass panic, hysteria and would make everyone hella religious depending on how early we detect it though we might have some time to make good memories before we die. atleast I would prefer a black hole smashing into us unbeknownst to us instead of a known star. Also no one would want to show up to jobs and stuff