So my cbet is profitable if villain only folds 36% of the time? And how did you calculate it?

The simple way to calculate it is the following:

You are risking 0.5 to win 1. Required fold equity = Risk / (Risk + Reward). So the answer is 33%.

The method assumes that your hand is complete garbage with no equity at all. So you only win if you make the opponent fold.

So it is a huge profit to cbet in position. I knew it was +EV. But not this much tbh.

Well, you should not use this calculation to create a strategy: that depends on your opponent.

If you start c-betting garbage all the time, and they catch on and start either calling you more, or raising you more; you're going to lose much more by the counter-exploitation, not only on this street, but on future streets.

Nobody likes to be exploited, and if you make it really obvious, eventually they'll catch on. Counter-exploitation is usually much more effective than exploitation, so even if they take a long time to catch on, they can still hurt you enough in a very short time afterwards.

In general, it's good to have a somewhat balanced strategy, and have some small deviations based on your opponent's leaks.

Just because a play is +EV or auto-profits from betting does not mean you should.

The strategic option of checking-back is always >0EV as any hand will be able to realize some sort of equity versus a portion of your opponent's range.

Also, if you c-bet at 100% frequency it is very easy for your opponent to counter this strategy by raising you liberally. When this happens you will be forced to fold a lot of hands that could have gained EV by checking back. Not only this but your opponent will be effectively reducing the EV of your range because you will have put money in the pot and then folded.

With every play in poker there are many moving parts and the fact that you are taking the time to ask these questions will help you 'put the pieces of the puzzle together' in the future.

Keep it up!