It’s an interesting question. The large books - like Barrons which we used - will have the school details and will have some intro pages - which won’t go into depth.
I think the best case is to get her to an area with multiple colleges - and just walk around - a couple big ones, a couple medium, and couple small. The reason i say a couple is - we took my daughter to Dennison and she hated it - it’s so spread out. Her current school is larger population size, but more compact (or it seems to me).
I think by going and seeing - wow, there’s so many people…or on a football day…it’s overrun. Do I want that? Seeing the big sorority houses like at Alabama - do i want that…or it’s too much. This one is an hour from a city. This one is in a city.
Not saying to sign up for tours. Maybe just a few Saturdays now that school has started - or a weekday if she hasn’t yet started school - go visit a couple colleges a day over 3 various days - walk the campus, have lunch nearby or in the student center, see the surrounding area (grab a bagel or do a little shopping). See if an overall environment clicks.
From there, you can narrow down - because you might say, she likes the bigger schools but not 300 person classes. Well many big colleges today have Honors colleges where that can be narrowed down, etc. In other words, you can make a bigger place small but not vice versa.
As for no clue in what she wants to study, that’s no problem. Most kids don’t nor should they - that’s why you explore. For those that do, many change.
If she’s unsure but it’s a liberal art or science (pscyhology, english, chemistry), you can pretty much go anywhere.
if it’s soil management that’s a possibility, then you pretty much can focus anywhere.
Different schools by admission level or requirement might behave differently. In other words, a student at a large elite school like Michigan, that is residential, might be different than a non-elite large school like Middle Tennessee, which is less residential, etc.
Students at Swarthmore (elite, small) might be different than students at Eckerd (small, but on the beach and while solid, not elite) - different in study habits, party habits, personality, political-ness, etc.
Personally, I’d casually find the alleged fit from size, geography, weather, sports, greek life (not that you have to participate - but some schools it’s huge, others it’s non existent). My son goes to a huge greek school, joined…wasn’t for him. Left…it’s no problem, etc.
So i’d start with some casual visits to 6 or so schools - and see if there’s a “pull” toward one type. If there is you can verify it.
If you vacation, you can add a half day “on the way” if you drive - or do a nice parent/daughter field trip - mix a hike with let’s spend an hour walking around here, etc.
Good luck.