Lovely ideas - i love doing stuff like this with my kids some of our ideas…
Make and put out a bird feeder (toilet roll, peanut butter + seeds or fat ball type ones)
Send some undies to Smalls for All
Colouring books/pencils to local hospitals childrens ward
Smile at everyone you see day
Paint some rocks with positive messages and hide them on a walk
Clear leaves for neighbours/something helpful
Plant a tree (with forestry scheme or an actual tree)
Donate outgrown but decent shoes to somewhere like Sals Shoes
Make Christmas ornaments (salt dough, paper snowflakes, handprint reindeer etc) to give to family
Post a card/picture to someone
Have a look to see if you have a local hygiene bank to donate some items to them
Also have a look for any local appeals from women’s refuges and items for refugee appeals
Buy a meal for a key worker - million meals/Uber eats (not sure if they are still doing this)
Look for a giving tree in a local shop (dunelm near us did this last year) or a wish list local organisation - school/animal
Fresh produce for local animal rescue - donkey sanctuary take carrots and ginger biscuits, our local Guinea pig rescue loves veggies