Some folks do not believe that 'freedom of religion' extends to freedom "from" religion in the US.
However, there is the concept of separation of church and state so, for example, at public/state schools we cannot really talk about religion, especially personal faith. The exception might be a religious studies class in high school. In fact, some elementary schools have banned the religious parts of holidays to the point where Santa decorations are okay, but nativity decorations are not. I can talk about Santa, reindeer, Elf on the Shelf and their ilk, but no baby Jesus. We can have Hanukkah lights and dreidel, but no stories of the Maccabees.
So, it's complicated. And weird.