Ideas for cheap, zero prep foods that can be eaten on-the-go?

I need to preface this with the fact that I'm disabled, and while I enjoy cooking, it is incredibly difficult for me to do and I rarely have the energy for it. YES, I know things would be cheaper if I could either cook regularly, or cook in big batches, but these things are not realistic for me. It's taken years of going to bed hungry to avoid cooking and wasting tons of food to accept that it isn't realistic for me. I've guilted myself plenty over the years, it does not help.

I am not in so bad a position that I need to count every penny, so I'm willing to sacrifice some money to make sure that I eat regularly - which has been an ongoing issue for years. I need to take care of my health first, which unfortunately means I need to spend a little more on food and medications than most people probably do.

Okay preface aside, I'm getting sick of oatmeal every day. I need some alternative zero effort but affordable food ideas.

Right now I bring oatmeal to work, and cook it in the paper coffee cups they have there. I'm at work for 10-ish hours, and then I go home and usually eat canned soup. This winds up being about $3-$5 worth of food a day? Depending on if it's a ✨Fancy✨ soup or not.

I can afford more than this, but I feel really guilty spending money, so I try not to. Anything I don't eat becomes savings, and then I start skipping meals to save, and... I'm working on that problem, money guilt is kinda hard to overcome, but that's why I had to preface that my health has to come before money. It's been hard for me to accept that fact, and I'm still learning.

Other foods I keep around:

• Trail Mix (can also be added to oatmeal)
• Cereals (Can't eat this at work unfortunately, and I often do not want it for dinner. It usually becomes weekend brunch.)
• Ramen packets (I have a hard time finding the energy to cook these, so I might pay the extra 30-50 cents and go back to the cups of ramen. Also you can crunch up the noodles and add them to salads or pretend they're weird foreign chips and just eat them plain.)
• Potatoes (Can be cooked and eaten at work, but they cool down very quickly and I can't leave my station to reheat it, so potatoes are only for long lunch breaks since I really cannot stand room temperature potatoes...)
• Bananas (Eaten plain or added to oatmeal. Technically I'm allergic to bananas, but only the skins, and not enough that I've ever needed to worry about it. Any banana could be my last tho if the allergy gets worse. Probably still worth the risk.)
• Lunch meat (to be eaten plain, I can't do bread for some reason, my brain doesn't allow it, but at least if it's just the slices I can eat it at my station. Just gets kinda gross warm.)
• Probably at least 2 other things I've forgotten and will feel silly about forgetting

Anyone have any more ideas for food that can be eaten in the car/at work with minimal effort? Things that can be tossed in the microwave or can be nibbled on throughout the day?

I've eaten so much oatmeal, it's so cheap, but I really need another breakfast at work idea before I lose my mind. It doesn't even have to be breakfast, I just need to be able to eat it without looking at it and have basically 0 risk of it spilling if I bump it with my very clumsy arm (this is why I can't have cereal at work.)

I feel like I have to be forgetting something obvious here.