Need Healthy eating advice

So I am 52 years old and weigh 235 lbs. would like to drop some weight while driving but am limited to not having a refrigerator. I am sure my metabolism is down. What are healthy options for eating OTR that you all have found? And are there any Supplements that may help while sitting down for 11-12 hours a day?
I currently drink only water with lemon juice (no soda or energy drinks). I have been trying the packages with the nuts and cheese but find myself still very hungry. So I end up eating at the truck stops and I need to find a way to stop that.