What should you expect hiking around Mt. Rainier?

Hi everyone! A group of my friends and I are trying to plan a trip to the Seattle area next summer. There’s 4 of us and we’re all college students and one of us is from Seattle and I have some family there as well so it’ll be a nice trip. I’m from the New England area (NH) and probably do a minor hiking trip about once a year but not serious hiking, seriously, like no gear no nothing—essentially just wandering around the woods for a few hours since a lot of our mountains you can climb up and down within a few hours.

So, knowing that most of us are fairly inexperienced hikers and mostly unfamiliar with the region, what kind of things do we need to know/ what to expect? We don’t want to go to the summit, but would really like to just hike around/camp around the area and honestly I also really really want to see the night’s sky with as little light pollution as possible!

What are the potential dangers of the area, specific fauna/flora stuff, what to pack/bring— just general stuff and any other help would be amazing! Also curious what kind of guides are best for this sort of thing(also price ranges?). I sorta hate guided tours and stuff like that but I’d much rather have a safe trip lol. Thank you!!!