I relate to some of the things you wrote, as I'll eagerly demonstrate below.
1. Do you have any traditional lunch or dinner?
Yep. Dinner on the 24th and lunch on the 25th.
2. Do you follow your country traditions or your family have their own traditional foods/drinks? If so, which ones?
We follow mostly Portuguese traditions, I guess. We have cod for dinner (on the 24th) with some steamed veggies, although it's not only consumed during this time of year. We eat a lot of shellfish too. At lunch on the 25th we usually have roasted turkey and duck.
This season is mostly an excuse for us to drink (not that we needed it). We have so many drinks it's insane. Mostly homemade fruit liqueurs, like Ginjinha (made with cherry, sugar and the most strong aguardente we can find) served in chocolate cups, Amarguinha or Amêndia Amarga, made with almonds. Pear, apple, grape liqueurs are also common.
3. Do you cook all your food or just buy everything at last minute already prepared?
Everything is homemade.
3. What's your favourite Christmas food (candies may be included)?
Definitely the turkey and the duck. And almost every single dessert (we have
dozens probably more close to a hundred).
4. What's your favourite Christmas drink?
Ginjinha with those amazing chocolate cups and the Amarguinha.
5. What's your least favourite (as in, you absolutely hate it and it should be eradicated from existence) Christmas food?
CRYSTALLIZED FRUIT. I don't even understand why such thing exists. It makes no sense why people like this abomination, and definitive measures should be taken to spare the world of this mutation.
6. And drink?
Champagne. I'm glad we don't have it as a tradition in this house.
7. After the festivities, do you regret the quantity and quality of food/drinks you shove down your throat or #yolo an #noregrets all the way?
No regrets. I see this holiday as the perfect excuse to eat and drink everything all the time and not be mocked to do it like a man.