There are lots of these sort of meal plans out there but, before you look at those, have you addressed the issue with actually preparing food? Because, for example, if this is a struggle, a lot of these meal plans take a fair amount of work which, based on your OP, I'm not sure you're up for?
What level of effort do you feel you are up to making? Are you literally just eating instant soup and sandwiches currently? And how much of this? Because realistically, proper food is unlikely to be significantly fewer calories, but will be 10000 x healthier.
Overall, a good way to meal plan is to write down a list of meals you can/are willing to prepare and eat. ideally, you'll get a wide range of types of foods, lots of different fruits and vegetables (including nuts, pulses, legumes) and you'd keep fats generally quite low. Depending on your preference and diet, perhaps reduce reliance on carbs to fill you up, replacing with vegetables/pulses etc, or increasing protein.
A few ideas you would consider adding to your meal plan that involve little cooking/prep and are generally quite low fat/lower calorie could be
Salads - buy bags of mixed leaves for variety and health then add additional chopped raw veg as per your preference (carrots, spring onions, onions, tinned sweetcorn, tomatoes, cucumbers, peppers are all good basics. You can get fancier and more complicated if you want to). Add a protein source - lentils, chicken, fish. Drizzle of oil (to keep calories down) and a squeeze of lemon juice of vinegar.
Home made soup - ideally made in bulk and stored in fridge/freezer to reduce reliance on regular cooking.
Grilled/steamed chicken breats or fish fillets with steamed vegetables.
Egg based dishes such as omeletes (with veg or a side salad), quiche (go easy on the crust if you're looking to keep calories down), scrambled eggs on toast with smoked salmon/ or ham, poached eggs with wilted spinach and grilled mushrooms.