I’d just add that, while Bio is the most common route to med school admissions, it’s by no means a requirement - and there’s some evidence that med schools are looking for matriculants with alternative backgrounds - admissions rates for non-BIO majors can be higher than BIO (although there are obviously a lot of factors that can play into that.)
Of course, you need to get that solid core of coursework that prepares you for the MCAT, in Bio, Physics, Chemistry, etc, but that can be done with an alternative major (though it is more work.)
Having a solid number of hours in “research”, preferably in basic sciences like Bio or Chem, is also required, and as @hedgehog12 noted, that’s probably much more accessible at W&M. IIRC, 200 hours is sort of the floor for your AMCAS (but don’t quote me on that, it’s been awhile.)
The thing about med school is, while the preparation for the MCAT is do-able under a different major, you still have to fulfill many basic “requirements” - the aforementioned research hours, community service hours, and clinical hours, in addition to preparing for the MCAT. So, it’s best to make a commitment to “pre-med”, to include those those extracurriculars, fairly early on so that you can be competitive in med school admissions. And, of course, you must maintain a fairly high GPA while doing so - a double-major courseload, plus your extracurriculars, might threaten that SciGPA.
In my opinion (and it’s just an opinion), you’d have to weigh the likelihood that you’ll be going to med school - if you’re 100% certain that’s where you want to be, then W&M will probably support that a bit better than UVA for reasons of research availability and a less-competitive atmosphere. If there’s a significant likelihood that CompSci is your intended career path, than UVA will probably support that better.
And finally, there’s the environment - each school has a rather different “environment” (the sum total of a lot of things) - some people will have strong preferences in that regard, while others would thrive in either environment. I’d suggest you consider that as well - you don’t want to be miserable for four years, no matter how good the decision looks on paper.