There is some debate as to what time Christ was actually born. While virtually all scholars agree that he existed,* we are not sure about when he was born. Many scholars argue that given that the nativity accounts claim that shepherds were grazing their flock, a December birth is unlikely, and therefore, a summer birth makes more sense. Others respond by noting that winters in that part of the world are mild, and that it might have been possible.
Christmas Day is also the date of several pagan holidays (probably because of its proximity to the winter solstice,) leading some to claim that Christmas is actually a pagan holiday, and that Christians who celebrate Christmas are actually celebrating the pagan gods. This is of course silly. My friends celebrate my birthday on March 4th. There are hundreds of people who celebrate birthdays on March 4th, but we are not all the same person just because we share a birthday.
In the end, does it really matter when Jesus was born? No, it doesn’t. All that matters is that He was born, He died for our sins, and because of that, we love Him by obeying Him and His Church because that is what will bring us to heaven, that is union with God.
Does that help? God bless!