I have done it over the last year.
80% of what we buy is completely unprocessed (ie milk, eggs, fruit, veg, meat, pulses, nuts, honey, oats, brown rice, herbs,).
17% is processed -flour, bread, Greek yoghurt, pasta, rice noodles, cheese, fruit juice, marmite, oat cakes, nice chocolate, fish fingers, oven chips (with potatoes and oil only), pesto, humus, ice cream (one with predominantly milk, sugar and chocolate), tins of pulses and tomatoes
3% Utraprocessed - Ketchup, fishfingers, chocolate biscuits, baked beans, rice pudding, pizza (though often make our own).
We eat
Breakfast - yoghurt with chia seeds, berries, walnuts and honey or porridge.
Lunch - salad with chicken or eggs or three beans, or an omlete.
Dinner- 100s of things. Meat and 2 veg, curries, noodles, pasta
Snacks - I quite often bake flapjacks or biscuits or have shop boughr or humus and veg sticks, fruit.
The kids will sometimes have fishfingers and DH loves a pie.
It has been really easy. Get year head around processed V Ultraprocesssd and aim not to buy it.