Yes. How else could children get presents while they're sleeping in houses with the doors and windows locked when the only other people in the house are their parents?
Are you a child? Maybe you should leave the adults to discuss things on sciforums. This might not be the best place for you.
When I was a child, we had a book of kids' jokes, a small, illustrated thing. But in addition to a weird bit of personal lore associated with the book (a dead painter who might have seen the same book, for having illustrated a punch line to a different joke therein), there was also this: Q: What goes up a chimney down, but cannot go down a chimney up? A: An umbrella. The illustration was an all too happy Santa Claus rocketing out of someone's chimney with a closed umbrella, and I think in the second panel we could see his cap sticking out from under the open umbrella that didn't make it down the chimney. • • • Yes, and a fat, happy Buddha is anti-Buddhist propaganda. In either case, the fact that an idea catches on says more about the people who believe, than anything else. I don't know the specifics about how chimneys were built in 1812, but it appears the chimney story is a nineteenth-century American tale first told by Washington Irving.
Given that some smoke conduits are too narrow (stoves) or are flues serving the gases of other appliances, Santa and his sleigh/reindeer shrink down to subatomic particle size in terms of travel and entering a residence. Deposited gift packages are timed to enlarge to normal size after a couple minutes. In addition, this shrinkage allows actions clocked micro-incrementally along the spectrum from attoseconds to zeptoseconds to yoctoseconds, so that Santa can globally visit the millions of applicable abodes in one night.