It depends both on the school and the major.
For someone who is truly undecided, a LAC can be a great choice. Many “mandate” exploration through distribution requirements and many also support multidisciplinary majors, often of a student’s creation. There are non-LACs that work this way too, like Tufts. Most expect that you will declare a major by spring of sophomores year and many departments put great profs into the entry level classes to make sure students have a great experience in their first exposure to geology or philosophy or art history.
One thing you may want to do is look at course requirements in a couple of areas of interest and think about how, at your various targets, you would go about maximizing your flexibility for a 2-4 semesters while your interests emerge. For example, if engineering may be of interest, there are a lot of foundational classes you would need to have completed to move on to more specialized classes. Someone considering international relations will almost certainly need to be taking FL to reach the level of proficiency for that degree. In some cases, this might require applying to a specific school or major simply to register. At others, it’s just planning appropriately.
I would advise at any school that requires admission to a particular school or major that you find out which are the hardest to get/transfer into. If it’s CS, for example, and there’s little interest in that now, it’s a hypothetical problem that deserves little worry.