Here's a list of programmes known to be scheduled for transmission over the Christmas period:
https://ukchristmastv.weebly.com/confirmed2021.html
I'm worried that Jools Holland's Hootenanny isn't listed for New Year's Eve yet but, as it didn't join the list until late last year, I'm still hopeful. There's not much in the the list that I'll definitely watch but I'll probably view . . .
Shaun the Sheep: The Flight Before Christmas
Live at the Apollo Christmas Special
QI Christmas Special
Spitting Image Christmas Special
The Voice Kids
Terry Pratchett’s The Abominable Snow Baby
. . . and, because I'm a big kid at heart, the CBeebies Christmas Show: The Night Before Christmas.
For some old favourites, I'd like to watch Blackadder's Christmas Carol, The Muppet Christmas Carol and the Christmas edition of The Good Life ("Silly, But It's Fun") where Margo doesn't get her delivery of Christmas goodies and has to rely on Tom and Barbara to make Christmas special for her and Jerry.
For movies, I'd love to see (but know I won't) anything on this list:
https://coucoufrenchclasses.com/the-top-8-french-christmas-movies/
alongside some great family movies, such as Time Bandits.