Hi tarriance
Let's see...
I have a salad every day for lunch where I can. Salad bits are pretty cheap. I have it with egg mayo (again pretty cheap to make) or chicken (from frozen).
Try batch cooking spaghetti Bolognese- Aldi is ideal for these ingredients. Super cheap. I fluff it up with other veg too... canned/frozen peas, sweetcorn, carrots, mushrooms, kidney beans... you can squeeze loads in there to really spread it out.
Fish pie - frozen fish bits (don't go for the smoked stuff unless you want your house smelling of fish for weeks😂), cornflour, butter, milk, cheese for sauce. Mash on top. Ideal.
Frozen veg and frozen chicken are always ideal to keep in the freezer and just whack out for a simple meal.
Jacket potatoes, beans on toast, pasta bakes (again fluffed up with various veg or tuna), omelettes are good too and finally soups. I made a super easy cheap soup the other day. See upthread if you want that one 😊
Hope you can take some of those ideas.