Hero(UTG) just under 200bb
Villain(BTN) 100bb effective

Hero 3x's 44 ($.15)
Villain 3x raises ($.45)
Hero calls

flop: 10 6 6r
Pot:$.97

Villain bets just under half pot ($.46)
Hero calls

Turn is 8 of hearts bringing possible bdfd

Villain check
Hero check

Turn comes off suit 9

Hero checks
Villain bets just under Pot ($.90)

This is where I butcher the hand and things get messy, I think the standard thing to do, in 3bet pot once the turn goes check check is to put out a call as it says AJs+ but I instead decide to put in a massive raise hoping to fold out his hands that had me beat like a 55 or A9s or A8s or prompt a hero from AKs. My question is should we ever be bluffing in this spot or just calling?

I reraised to $3.60 btw which... yea

how is villian btn if you check back turn? It's important to know the positions.

One question: what would you be bluffing Villain off? Seems odd that Villain would want to re-raise a preflop UTG initial raiser with 55, 66, or 77. Villain could have reraised preflop with a medium Ax if he thought you were opening too wide. Those things are possible, but don't seem likely enough to make it worth the bluff.

What are the positions?

youre probably better off folding. he prob has what youre trying to tell you have