Preflop looks standard
Flopping a monochrome board is going to kill a lot of villain hands. Hero should be c-betting wide and villain should defend wide. Small bets work fine. Villain will fold his "no pair, no spade" hands a lot.
The turn is not quite a brick, but it certainly didn't help Hero's hand. Villain is often ahead here and not likely to fold. Hero isn't going to survive a check raise. Let's take the free card.
The river is tricky. What sort of hand could villain have that calls a river bet? Maybe a straight? The queen high flush for sure. Perhaps even a ten high flush.
What is Hero's plan if he gets check-raised? It is hard to fold that king high flush. I suspect Hero is going to call down much of the time.
So, does the risk of losing to the better flush overwhelm the potential of value? Yikes! That is a tough question. And perhaps why this hand got posted.
I think Hero needs to get some value from his flush. But the bet has to be small enough for villain to call with much of his range. Let's try $1. Hero will call a small check raise - but only a small one.
It was hard to ignore the hand is a posted one here. I expect villain is about to take Hero to value town. But only because the hand is flagged as being special.
DrStrange