I am about to turn 40 and have been about size 6-8 for about 20 years.
Breakfast is overnight oats, an omlette, porridge or a smoothie bowl topped with granola
If I need a snack, it is a peice of fruit, a cereal bar or a cappuccino
Lunch is a sandwich and raw veggie crudités or salad with some cous cous, quinoa or a slice of bread
Afternoon snack would be fruit, nuts or a couple of rice cake with hummus or peanut butter
Dinner is pasta, rice or potatoes with a protein - beef, chicken, fish or tofu, etc and plenty of veg. This could be as a spaghetti bolognese, chicken or lentil curry, chicken, veg and potato traybake, poke bowl, etc
After dinner, I always have a sweet treat, I crave a bit of sugar/chocolate in the evening so will have either dark or milk chocolate, a homemade brownie or biscuits, an ice cream, whatever I'm in the mood for really.
If I've got a holiday coming up or my clothes are starting to feel a bit tight, I'll cut out the snacks for a week or two and just have my 3 meals and replace my evening treat with an apple or a banana. That usually just helps to keep my clothes fitting nicely.
I used to exercise a lot and was proud of my muscle definition, but with 2 young kids I don't have time to get to the gym so the only exercise that I do is walking