Learn to delegate!
My mum always did - as kids from fairly young age we would prep/peel veg and even my dad (who is definitely no cook) did pigs in blankets and stuffing and laid the table.
I'm a single mum so most years it's been just me and dd and quite honestly I've mostly done "cheat" versions, I'm fussy and also I'm veggie and dd isn't (although she eats veggie dishes too she likes turkey, pigs in blankets etc) so obviously I wasn't buying a whole turkey just for dd! And honestly the ready made stuff especially in recent years is pretty good quality.
So...
Turkey Breast fillet for dd
Veggie main for me - varied greatly over the years has included quorn fillets, quorn roast, quorn peppered steak, veggie Kiev, veggie wellingtons of various descriptions, ditto pastry plaits - there are SO many options now it's great
Ready done pigs in blankets for dd (she prefers the chilled version but I'd cook some on Christmas Day and she'd have the rest for a snacky lunch Boxing Day)
I have veggie chipolatas
Frozen or chilled ready to roast potatoes
Frozen Yorkies
Ready Prepped glazed parsnips or other ready to roast/cook veg
Ready made cranberry sauce
Paxo sage and onion stuffing we both like that's dds "job"
Bisto gravy again we both like
My mum is a great cook and quite traditional but even she now uses frozen roast potatoes and yorkies and yes foil disposable trays to reduce how much washing up there is.
She has the additional challenge these days of creating a "soft" version for my dad so very well cooked meat (they don't actually like turkey so it's always been a slow cooked ham at mums), mashed potatoes, well boiled carrots, stuffing, and he gets yorkies still but she soaks them in gravy so they're soft for him.
Yes to physically checking you've got what's on the list - one year at mums there was no stuffing
what happened was ingredients weren't in shop when she did that shop, she meant to go back and get but forgot and got it in her head she HAD bought it as it was on that shopping list.
Also do a timetable start with the serving time and work back - then add 20 mins as SOMETHING always happens to put you off track and nobody ever complains if it's a bit early but they do get hangry if you end up running late.
And yes to limiting especially little ones what they're eating before hand as they'll just fill up on selection box etc otherwise
We also do the starter a good while before the main and have a break, starter can be soup & bread, salad, dd likes a seafood cocktail sometimes.
Dessert is often not had until the evening I like mince pies and Christmas pud but dd isn't a fan, too rich for her so she will have things like choc mousse or syllabub with amaretti biscuits or profiteroles
I'm sure you'll be fine. It's one meal on one day, not the end of the world if it doesn't go perfectly - the imperfect ones just become funny family anecdotes - like the time my aunt was feeding 15 (inc toxic in-laws!) and was all organised - but didn't turn the oven on and only realised when she went to put the veggies in that there was a very cold uncooked turkey in there! Or the friend of mine who laid on a feast for her new husbands family only to be told when it was too late that new mil was allergic to garlic, onions etc! Mil ended up having just the starter (Seafood cocktail) some steamed veg and some ham friend had in fridge for next days buffet, and dessert. New husband to blame on this one - idiot! He was with her when she bought and prepped all the stuff with garlic/onions/shallots etc and never said a bloody word!! His mum tore into him later when it was just the 2 of them and apparently was very understanding and gracious to friend but friend was still mortified.