Do you use a comma before the word apparently at end of sentence?

You don't use a comma before "apparently" at the end of a sentence. "Apparently" is an adverb, and adverbs generally don't require a comma before them.

Here's an example:

* Incorrect: He was late, apparently.

* Correct: He was late apparently.

The only time you might use a comma before "apparently" is if it's introducing a contrasting or parenthetical statement. For example:

* Correct: He was late, apparently because he forgot to set his alarm.

In this case, the comma is used to separate the main clause from the parenthetical clause that explains the reason for his lateness.