Fresh as a newborn baby!
Dairy, fat and protein are a supposed staple in any diet, just as they are delicious. Them, along with fruits and veggies are hard to keep fresh and managed on a student's schedule. The primary reccomendation here is to keep them to a minimum, getting them knowing you'll eat it within a few days to a week.
This one's plain and simple. Some kind of milk carton is always good to have. Good tip: the less fat in the milk you buy, the farther away the expiration date. So, make sure you know your frequency of using to get the most out of your milk.
Sliced meat and cheeses are great, but they go bad quickly. Other options include refridgerated microwave meats, like pulled pork or brisket. They're a bit pricier, though much more delicious than anything you can make in yourself in a dorm. As for cheese, shredded cheese and plastic cheese are a must in the fridge. they're cheap, they last almost forever, and they're tasty. I mean, who doesn't have a Kraft single in their fridge?
Fruits and vegetables are best used and eaten within a few days of getting them. Though, the prepackaged fruit cups and bagged veggies last a little longer and are more managable space-wise. Citrus and carrots are probably your go-to's if you want to keep wholesale produce in your fridge for a decent amount of time. Preserved produce will also last a while.
The condiments to keep completely come down to preference. Ketchup, mayo, hot sauce, and other all-purpose ones are far better for taking up space than individual ingredients like rice-wine vinegar or oyster sauce.