Hi Isabella, and welcome.
Best wishes to your boyfriend while he's on the road. Since he'll have access to cooler(s) on the road, could you prepare a few pieces of fried chicken for him? Not a lot, just what you think he will use within a couple of days....maybe a few slices of roast beef or ham, and some sliced sandwich cheese so he could make his own sammies. A small tub of cream cheese with some pre-sliced bagels could be breakfast for a couple of those days, along with bananas, apples and/or a bag of small clementine oranges.
Bagels, pita bread or pita chips, crackers, a jar of peanut butter, and a jar of honey if he likes it, would work for non perishables for that short of time on the road. As another suggested, granola bars is a good idea, too.
You've probably already thought of this, but life on the road will be easier and more pleasant for him if he has a large ziplock bag filled with disposable plates and cutlery, napkins, small travel sized salt and pepper containers, a can opener, and some Clorox handwipes. A few plastic grocery bags would be helpful to hold trash in until he can get to a trash bin, in case he just wants to pull of the road under a shade tree and eat.
Hopefully he will be traveling in a state with nice weather this time of year!