THE BELOW MESSAGE

No, it’s “the message below” or “the following message”. Pick a lane.

“Below” is used as a stranded preposition in your case (the more generally accepted usage), whereas the original post uses it at an adjective. While usage of “below” as an adjective is not universal, it is still accepted by some dictionaries. I could find only the Webster English Dictionary as an example, so I suppose it’s mostly exclusive to American English. So yes, your example is the more universal mode (as well as my personal preference), but American English generally accepts the above usage as proper grammar.(The sentence above, as well as this one, demonstrate the usage of “above,” a relative locus, as both an adjective and a preposition in modern English).

It took me way too long to realize that all words and grammar were made up by some one at some point while they were being silly. Ever since then I came to the conclusion that people can speak however the fuck they want so long as I understand them.