A “Fact” means something that is unquestionably true. Merriam Webster says it is the “quality of being actual.”
“Factoid” has two distinct definitions, one being more or less a
subset of “Fact”, the other not meaning the same thing as “Fact”.
The first definition is: “an invented fact, believed to be true
because of its appearance in print.” The second is from
Merriam-Webster: “a briefly stated and usually trivial fact”.