For lunches I like salad with plenty of leaves - I try to buy nice bags of mixed ones with different textures and flavours so it's not too bland. Generally have chunks of cucumber, cherry tomatoes (again I buy the nicer varieties so they're actually enjoyable to eat) and any other veg - I really like raw broccoli chopped up fine, peppers, cress, raw mushroom, sweetcorn, sugarsnap peas - despite my size and bad habits I do really enjoy vegetables so make sure you are choosing things you will take pleasure in eating - if you force down things you don't really like I think you'll be more likely to break. For protein I'll generally add a cold boiled egg, crustless quiche (Asda do mini ones in lots of flavours that are cheap and tasty - I usually eat half with lunch) some grated cheese. If you don't want a veggie option I used to really like chopped up chicken breast (cooked the day before with bbq or fajita seasoning) or some tuna. I like a wee drop of coleslaw too, I'm just careful about how much I add (very heaped teaspoonful is enough to act as a dressing/satisfy me, whereas before I'd be ladelling it on).
If you're not keen on plain salad, there are loads of "thin" bagels/ sandwich thins etc. I try to buy the protein/wholemeal ones.
Sometimes if I think I've made too much dinner, I'll portion off some in advance and use that the following day for lunch. I find if I put too much on my plate I'll over eat whereas if I remove some before I plate up it takes the option away. I really enjoy cold, leftover stir fry and sometimes add in the gyoza you can buy from the freezer - you can have quite a few of these without too many calories.
If you're at home, an omelette is a nice lunch and you can add whatever you like - lean bacon with the fat cut off, veg, cheese etc.
Snack wise during the day I have stuck to fruit or veg and some nuts (or Pom Bears!). I bought myself some little snack pots and take two or three to work with cucumber chunks, sugarsnap peas, grapes, raspberries, tangerine segments. I really like the baby cucumbers you can buy for snacking - if this is too plain you could add hummus or low fat yoghurt/ cream cheese as a dip but I don't bother. I try to keep my chocolate for after dinner if I fancy any but if you prefer something sweet on your tea break have it then and have fruit for after dinner instead.
I think for me it has boiled down to making everything as clean as possible whilst still being enjoyable. I have a pal who eats dry rice cakes at lunch time and there's no way I could keep that up.
I've been out for dinner and had a takeaway or two as well - I've just tried to be mindful and not go overboard - choose a small portion when I might normally have a large, follow my meal with a really nice coffee instead of pudding etc. Again, going veggie has helped as I find it easier to have some vegetable pakora instead of a full blown chicken curry with all the sides.
I get half an hour for lunch and depending on my day I will sometimes use that for a walk and eat lunch as I work, or sometimes 15/20 minute walk and eat quickly when I get back. Usually if I can I will walk to the shops after work or first thing in the morning too - I find I'm more likely to do it if I have a purpose rather than just going for a random stomp. Depending on your interests you could listen to an audiobook or a podcast while you walk. I've also discovered walking tours in my local area where you follow and listen via an app on your phone and you get a wee history lesson on the route.
Where I am, GPs can't prescribe Mounjaro - you do need to buy it privately however I think it's worth speaking to a GP or even a pharmacist of you're nervous about it. At the moment, everyone I know who uses it has had success but I'd follow some of the advice here and do your research first.
Sorry, I feel like my posts are quite long but I know how it feels to have a lot of weight to lose and these things are what's really helped without me feeling miserable and joyless.