Ok. Don’t panic!
Veggie of 30 years and on benefits here so I think I can help.
You will need (hoping you’ll already have most of this actually):
Bread
Fresh pasta (doesn’t need to be filled, tagliatelle or similar is fine)
Unflavoured cous cous or Quick cook rice - I tend to use cous cous as a rice sub as it’s quicker and easier to do
Cheese
Eggs
Potatoes
Sweet peppers
Mushrooms
Tomatoes (I prefer cherry myself)
Iceberg lettuce
Cucumber
Broccoli
Aubergine
Courgettes
Carrots
Large jar/s pitted olives
Passata
Tinned tomatoes
Tomato purée
Garlic (lazy garlic is great stuff)
Ginger (as above)
Soy sauce
Sweet chilli sauce
Diced onions (I get frozen much easier and cheap)
Budget tortilla chips (trust me people won’t notice)
Sour cream
Guacamole
Stock cubes
Marmite
Pesto sauce in as large quantities/cheapest you can find and you can make it go further by adding cream cheese or olive oil
Herbs and spices - hoping you have the needed ones in already or can adapt
Breakfast each day - “continental” as you said - so bread, cheese, fruit (needn’t be fancy, grapes, apples, bananas should be fine), natural yogurt, tea, coffee, fresh but cheap juice
Day 1
Lunch - salad with a base of lettuce, tomatoes and cucumber and additional optional cheese, boiled eggs, olives, sliced peppers, sliced mushrooms, make your own salad dressing if you wish or get a cheap but large bottle of a fairly neutral one.
Afternoon cake - start simple so as not to create high expectations - a simple Victoria sponge
Dinner - pasta with a simple tomato & herb sauce (passata, tomato purée, garlic, basil and oregano) and whatever veg you fancy using, I generally like peppers and broccoli with this but you could have thinly sliced courgette - whatever you fancy
Pud - meringue nests with whipped cream and fruit
Day 2
Lunch - sandwiches - cucumber, cheese, egg, quorn deli slices (the “ham” comes in a decent sized pack)
Afternoon cake - banana loaf
Dinner
Chilli - quorn mince, Tinned tomatoes, Passata, garlic, ginger, chilli. Serve with rice or cous cous, tortilla chips and guacamole and sour cream to dip
Pud - ice cream is perfect after a chilli and no effort
Day 3
Lunch - vegetable frittata - eggs, diced peppers, onion, mushrooms - whatever your guests fancy
Dinner
Mushroom stroganoff - onions, garlic, smoked paprika, stock, diced mushrooms, sour cream. Serve with cous cous or rice or even roast or mashed potatoes as it’s quite hearty and rich
Pud - a strudel would work well with this with ice cream or custard.
Day 4
Lunch - wraps - fill with veggies, quorn chicken chunks quickly fried off, salad items (lettuce, tomato) and dressed with sweet chilli sauce and/or sour cream
Afternoon cake - lemon drizzle - dead easy!
Dinner - pasta with veg and pesto sauce - give you a bit of a break from “proper” cooking mid way but still provide something tasty and filling
Pud - bought cheesecake or tiramisu (you can serve small portions of this if you use lovely glassware and “ice cream” fan wafers) - again gives you a bit of a break from cooking
Day 5
Lunch - toast/crackers and veggie pâté/soft cheeses, olives, cucumber and tomatoes
Afternoon cake - scones - bought or home made - I can’t make scones but maybe you can
Dinner - stir fry - sweet peppers, mushrooms, broccoli, thinly diced carrot, onions, garlic. Sauce - sweet chilli sauce mixed with soy sauce and ginger works really well. Serve with rice or cous cous.
Dessert - sorbet works really well after a stir fry
Day 6
Lunch - sandwiches again it’s been a few days so not too repetitive
Afternoon cake - iced ginger squares - easy but weirdly impressive
Dinner - hearty veg casserole - carrots, broccoli, courgettes, aubergine, as you like, potatoes, quorn chunks, all cooked in stock and flavoured with herbs, serve with crusty rolls and butter
Pud - gonna go retro and say apple pie and custard.
Day 7
Lunch - home made carrot and coriander soup served with crusty rolls and butter
Afternoon cake - chocolate cake - a little indulgence after the healthy soup
Dinner - vegetarian/vegetable pie you could use ready made pastry - with potatoes and veg
Pud - meringues again - light after a carb heavy meal
Day 8
Lunch - frittata or omelette
Afternoon cake - jam tarts topped with cream or yogurt - a little indulgence after a light lunch
Dinner - veggie curry - if you’ve a slow cooker all the better. Diced veggies (carrots, peppers, aubergine and courgette all work well), quorn chunks if you like, stock and spices as your preference , serve with rice or cous cous, poppadoms (home made it bought) and home made raita (yogurt, cucumber and mint dead easy)
Pud - I’d go with ice cream or sorbet again as that’s what I like after something spicy
Day 9
Lunch - mini pita pizzas - pita bread or even ordinary bread, tomato purée, garlic, basil, oregano, veg as preferred by guests - mushrooms, peppers, tomatoes...
Afternoon cake - fairy cakes - light and retro after the pizza
Dinner - ratatouille served with buttered bread or rolls or rice or cous cous or even pasta
Pud - sweet pancakes - home or ready made either way dead easy, serve with cream, ice cream or sorbet or as they are
Day 10
Lunch - as it’s the last day have a “free for all” to use up whatever’s left of the salad and deli items. Provide bread/crackers/wraps as guests prefer
Afternoon cake - as it’s the last day maybe go for a “showstopper” as it’s the last day - a Black Forest gateau is actually surprisingly simple and you could even use some cheats by using a shop bought chocolate sponge and adding the cherries and cream
Dinner - if they won’t stand for at least 1 takeout they’re pretty selfish and ungrateful but...failing that I’d do a big “shepherds pie” type thing bread and butter - kill em with carbs!
Pud - cake and custard
I know you’ll not follow plan to the letter but hope it gives you some ideas and helps you panic less.