Well, this is quite normal because the food industry has done a great job at confusing us as much as they can.
I would suggest you add a book called in "defence of food "to your Christmas list www.amazon.co.uk/Defence-Food-Nutrition-Pleasures-Manifesto/dp/0141034726?tag=mumsnetforu03-21
You need to take a step back from industrial or commercial start again eating from the basics. Abandon Ultra processed food and go to the fresh aisle. Leave anything that says " healthy" on the packet on the shelf and pick up a packet with no more than 5 ingredients listed and possibly ingredients that do not require a factory or high pressure machines to exist.
For breakfast, a wholemeal toast (with wholemeal flour, not wheat flour + bran), an egg if you like it, rolled oats with berries, ....
For lunch, become a salad wizard with fresh lettuce (not from a bag filled with CO2 and tasteless) , radicchio, or oven roasted veggies, with maybe a small piece (half your palm) steak or chicken breast or steamed fish, for dinner a soup, a dahl, a minestrone, or even a small plate of pasta with your own sauce.
Eat bread only once a day, and try to find a real bread not the typical soft loaf with an ingredients list that goest forever. When buying, anything with more than 5 gr of sugar, leave on shelf and do a cleanup of your kitchen (fridge, freezer, cupboards) if you are really serious about changing your eating habits