I apparently had an old-fashioned childhood... in the 1990's/2000's. It was cereal at home, but if I was at my grandparents', it was porridge, bacon sandwiches, or possibly a few slices of fruit loaf bread. Summer holidays meant foraging and making jam.
Primary school is responsible for introducing me to ultra-processed foods that Jamie Oliver subsequently banned. The rest of it put me off certain foods for life (anything lumpy, quiche, and the mere smell of mushy peas, which permeated the assembly hall, and often got squashed underfoot during indoor PE).
I stopped eating lunch at secondary school, partly due to severe anxiety, and because the dinner ladies thought I was fussy for asking for a plain jacket potato. I was not a fan of beans, and couldn't eat cheese due to migraines.
Dinner was usually meat and vegetables at home, or meat/fish, vegetables and a pudding at my grandparents'. Pudding meant something like apple crumble and custard. I don't remember eating cereal/
I went through a phase of a fair bit of ultra-processed food at university, but have since gone back to my grandmother's kind of cooking, like homemade soups, fish and vegetables, steamed puddings and so on. That's what I've had today, and I am stuffed! Admittedly, I do a lot of batch cooking (e.g. bread, pies, soups) so that I'm not reverting to ultra-processed food during the working week. I try to grow some of my own fruits and vegetables, which I am not very good at, unless they don't mind a bit of neglect.
I don't drink tea or coffee, and drink more water/milk than anything else. This is quite handy, because I am rarely in the mood to drive to the nearest town to buy anything else after work!
I don't eat much junk food, which helps on skipping around 90% of the aisles in the supermarkets.