Having lived in the dorms for four years as a student and RA ending just this last May, allow me to say: absolutely nothing.
Okay, well obviously she’ll need a towell and a notebook, but don’t go out an buys tons of crap for school. As others have noted, especially do not buy any type of appliance beyond perhaps a fan if they are without A/C. The fire-restrictions in dorms are extensive, and most any cooking device is almost certainly banned. Also, most dorm rooms now include microwaves and refrigerators.
Do your due dilligence with the college, not a random message board, and find out for certain.
Also, I’d highly advise that your daughter plan things out with your prospective room mate. Being able to plan the limited space together and will avoid making you the jackass residents/parents that unload half a U-Haul worth of expensive electronics and take over 3/4’s of the room before your room mate even arrives. Again, communicate with your room mate prior to coming to school if you must or just give your daughter a certain amount of money and permit her to decorate and furnish her room as she sees fit or simply pocket the money.
Also, illness in the dorms is common but by no means predestined. I had a lot of colds my first year but survived all four years without any major illness (even through a norovirus outbreak on campus, that was no fun), but fastidious hand hygeine really is key to avoiding illness. By my senior year, I had two colds all year even with working in a health clinic 25 hours a week. So, perhaps some bottles of hand-sanitizer to start her off on good habits.
For the sexual health issues, just remind her to bring it up at a visit with her pediatrician or family care doc prior to heading off to school if it’s relevant to her to discuss any options if relevant. Alternately, most schools also have student health services well versed is handling sexual health issues, just tell her to make an appointment.
A new laptop is usually a good idea, but she probably won’t need all of the picky things the college says she needs. The “great deal” offered by Dell probably isn’t. Comparison shop, and as with all technology, it’s probably best to delay the purchase until the month or so before she heads off to school.