[PantsOnFire]

The way you are asking the question, I assume you want answers in the NL language.

In NL, most decisions where you are using pot equity are all-in situations. For example you have 44 in the BB and a short stack has moved all-in on you. Now you have to range your pot equity with 44 vs. his possible range of hands and compare it to your offered pot odds.

The same might be true if you have that nut flush draw on the flop and are facing an all-in from villain. If your call odds are greater than about 2:1, then you call. If you figure your A is an out then your equity is a bit higher at (guessing here) 44%. So again, use this to decide to call given the pot odds.

However, when you are faced with a bet on the flop that is not all in, it is much more complicated. Since there is money left, there can be betting on the turn and the river.

NL Holdem is more of an art than limit holdem. So instead of being faced with calculating pot odds and equity on the flop in NL, you are thinking much more about implied odds and also fold equity. And to think about those two things, you need to have a good grip on what your opponent could hold, how likely he will fold to a bet, how likely and how much he will bet on the turn, and how much you could get out of him on the river if you make your hand. You also have to consider if a raise on the flop might get you a free card on the turn or win the pot outright. And you have to consider his style of play.

You can see in limit that it's a lot easier to get from the flop to the river with a flush draw than it is in NL.