It may be cold outside but there is still a lot to be done in the garden.
You can still do weeding. You can clear up the dead leaves. You can prune back anything that is dead. You can fill the bird-feeder.
You can bring in some green from the garden to decorate the house. Be careful with holly - wear gloves.
You can plant bulbs for the spring. If you like, you can plant a bulb in a pot. Put some soil in a pot. Stick the bulb into the soil so that just a little bit is showing through. Put a small layer of soil over the top. Keep it indoors in a cool, dark place. When the green shoots start to show, bring it to somewhere warm and sunny like a kitchen.
You can buy bulbs in garden shops. If there are none left, you can plant a garlic bulb or an onion.