One element that’s identical between fixed-limit and no-limit is this: once the river card is dealt, there is no longer any potential value associated with a hand. Draws have either been made or they haven’t, and no second chances for improvement remain. Every hand is fully realized, even if that realization isn’t particularly to your liking.
Your hand is what it is, and all you can do now is make the most money you with the winning hand, and cut your losses if you are beaten. Making the most money with the winning hand doesn’t mean that you need the best hand. You can always make money with the best hand by bluffing.
