Cyberpunk 2077 has quite a few different endings, some with specific trophies, and some not, but still count as endings. Depending on your choices and your actions during the adventure, certain options may or may not be available when the time comes. But have no fear, in the majority of cases there will still be time to go and unlock all this, after reaching one of the endings, the game automatically brings you back just before the point of no return with a special reward in your inventory. The other items obtained in this branch at the end are however lost. There is also no New Game Plus.
It's obvious, but huge spoilers await below.
Cyberpunk 2077: Point of No Return
The Nocturne Op55N1 mission which asks you to go see Hanako at Embers is considered the decisive moment. A warning message pops up as you approach, so you can't miss it and there is nothing to worry about. You will always be brought back to the elevator after the end, in order to resume exploring the world or testing a new ending.