I like low fat yogurt or porridge with berries and seeds about 250- 275 for breakfast
Tesco meal deal about 475 for lunch if you have a veggie sandwich around 400cal, fruit snack and water or vitamin drink. You could do it for less as there's an egg butty for about 250 or so but it's not the most filling.
That leaves me about 450-500 for tea which can be things like soup, bean stew, vegetable casserole, curry served on spinach, or a jacket potato (220g so not huge) with low fat cottage cheese and beans plus salad.
Or shiritaki noodles are fantastic if you're hungry and want a bigger portion as they add bulk but hardly any cals and I find them a more filling than just veg. You can use them with any pasta or noodle sauce (stir the sauce in, don't serve it on top as they have no flavour and use plenty of herbs or spices). I buy them in bulk off Amazon
I don't really snack much but apples, carrots, satsumas and baby bel lights are useful to have around. My treat tonight was a low cal hot choc (40) and a square of dark chocolate (72).
1200 isn't a great deal when you're used to eating whatever you want, as I was, but after a couple of weeks I am pretty used to it. I have knocked buying certain favourites on the head such as full fat cheese, houmous and bread (except for my sandwich). It's just easier than having tiny portions and wanting more.
You do need to portion control and check weights with this allowance but I don't bother to count the skimmed milk I have in tea and low cal ingredients like soy sauce or vinegar which make the recipes much more satisfying.