Depends on time of year. Some of roads aren't accessible in the winter.

I would check AllTrails app for most. You can filter by location, difficulty, and features etc. It’s also good for recording your hike, and making sure you don’t get lost. I suggest downloading their main layer and topo layer before starting hikes you’re unfamiliar with. They also have general weather for the day in there. And I use accuweather and the national weather.gov website as well. Visit the website for the park for some previews on hikes, perhaps. Not sure if they’re listed.

This may already be in the comments... but can anyone tell me what kind of van this is? And how long it is?

Its been several years for me, we stayed in the small town of Three Rivers right outside the park. Usually I love these park towns, but we didn't love this one. Nothing horrible to say, just not the friendliest, food so so and the like. On the other hand it was very close and you will love the parks.

Check out the app ioverlander. I found all of my free camping spots through it on my recent road trip

I recommend going on a "booze" cruise (tour included)! It's a full bar and the view is absolutely breathtaking. There are several, but I don't recommend the M.S Dixie II since they allow small children. Trails: Glen Alpine Trail to Aloha Lake Hiking Trail (long hike) + Cascade Falls Trail (short hike) Coffee: Clyde's Coffee shop (family owned, local, and they have the BEST apple strudel) Lastly, if you have time, I recommend paddle boarding at the lake. Have fun! These are all recommendations for SLT.