People figure out ways to have a little fun wherever they are. Penitentiary inmates might have fun playing cards. I bet if you were stranded on a desserted island you’d figure out ways to entertain yourself. Part of being human and a way of embracing the suck. I think some posts further above are talking about that sort of fun. You’ll encounter stressors and annoyances, but you’ll be in it with your classmates so you’ll just laugh about it.
But under a simpler definition of fun, activities that you’ll actually really enjoy, it depends on what you like to do. But I’d probably say not a whole lot, though there are definitely some moments like Temple described. But those are the exception to a typical day.
For example on a weekday you can’t just decide you’re gonna go meet people from class to study and chat during lunch. Until your 2/C year you won’t go out to bars on the weekends, if that’s your thing. Even if you don’t have a class until 11, you won’t stay up late watching TV with your friends becayse you need to wake up for formation at 6:45. Dating isn’t as common as at other colleges. And you have limited time for extracurricular clubs. Basically the time commitments on you cause you to have less opportunities to do whatever you want.
I’d say the focus is much more on becoming friends with the people in your company and then trying to see the positive in the stuff you’re forced to do. Enjoy playing intramural flag football. Complain about parade practice. Wake up early for a workout. Then take what little free time you do have on the weekends and dictate your own fun. If you’re lucky enough not to have duty on the weekend, plan a trip to DC or NYC.