Here is a good story of Jesus birth for kids. It was going to be posted on Christmas Day, but since there has been an inquiry, it will be posted now.
Superbook has a Superbook Club for children.
If you are still looking for a Christmas gift for a child, you might consider checking out Superbook.
CBN publishes the Superbook series. https://www.cbn.com/superbook/
A blog post can only introduce a topic but not cover it in depth. For more study on various topics, click here for links to various Christian ministries.
Depending on the ministry, there may be online church services, YouTube videos, podcasts, radio programs, books, teaching, or more. You have to seek out what they have.