Does the sentence grammatically work? he is truely the very John.

[NewHopeR]

I don't know whether "he is truely the very John" sounds natural.

(Background: John has been pretending to be Mr. Jo-Jo. He denies he's John - though everyone knows he's no doubt John himself)

John did a lot of dirty works in the past, which is why he dares not facing his true self now- he has lost his courage to
admin that he is truely the very John.

[SlickVic9000]

(Not a Teacher)

That's not the only thing that sounds unnatural. Here's my take on this:
"John has done dirty deeds (done dirt cheap, of course) in the past, which is why he dares not face his true self now. He has lost the courage to admit that he is in truth, John."

[charliedeut]

Also note the correct spelling of truly