I would say if you know absolutely nothing going into it, watch the saga films (episodes 1-9) in the order of 4, 5, 1, 2, 3, 6, 7, 8, 9. You get the two best films to start, and there’s a revelation at the end of 5 that if pop culture hasn’t spoiled it for you already is pretty mind blowing. Going to watch 1-3 at that point gives you the backstory of that revelation. Rogue One and the Solo spin off can really be watched at any point, but probably best to do them last simply because there are so many call backs and easter eggs that you may miss them otherwise. Someone above mentioned the clone wars tv series. The tv shows are all worth a watch. The original clone wars mini-series is great, the later clone wars series eventually finds its legs and becomes really good as well. Rebels captures the feel of the original trilogy really well, and the Mandalorian series is just awesome.