Q.care for trees during winter
How to protect trees and shrubs during winter and how often to water during winter? When is good time to plant trees and fruit trees?
Here are a couple of article outlining winter protection measures: https://www.gardeningknowhow.com/plant-problems/environmental/protecting-plants-winter.htm
In winter, plants are generally dormant, so much less water is needed. This article covers a general approach to winter watering: http://aces.nmsu.edu/ces/yard/1996/090996.html
It's hard to make a generalization regarding the planting of trees, because to some degree it depends on the kind of tree. However, almost any kind of tree will respond to planting in the early spring, when the ground is workable, but dormancy has not broken.