Yes try and get a click and collect slot, but if you can't just write a small list for your local shop.
It is just a roast dinner, so don't put loads of pressure on yourself. Keep things basic.
Meat to roast, couple of easy trimmings if you want - jar of cranberry, packet of stuffing or packet of bread sauce whatever you like.
Basic veg with one Christmassy addition - sprouts, parsnips or red cabbage.
Box of crackers.
Frozen Yule log/Christmas pudding/couple boxes of mince pies. Cream/ice cream.
Tin of quality street, boxes of chocolate fingers for the kids. Cheese, biscuits.
Nice soft drinks.
Buy some buffet style food to pick at on Boxing Day - ham, cheese, pork pies, sausage rolls, coleslaw, pickles, ready made salad.
Remember the shops will be open again right after Christmas, so don't panic and just get what you need to tide you over.
Christmas Day can be a pyjama day playing with new toys, your kids will probably love that more than anything you could have planned.
Feel for you, we've all been ill this week, I've got a shattered three year old with a barking cough, a poorly baby who may need a doctors visit and I'm down with it myself. Toddler's been asking me to make Christmas biscuits with him all week but I just haven't been able to and feel rubbish about it, but it is what it is, we'll still have fun, the important thing is to get everyone well.