What is the best way to make a cut scene that works with UI in the in-game?

Hello.
I’m working on making a simple RPG game.
Creates a trigger box in the viewport and plays the cut scene with the UI when it crashes. And I would like to implement an event where I get key input from UI to display the next UI and move to the next cut scene.
For example, when you arrive at the entrance of the boss map, the boss cut scene is played and the UI shows that the boss has appeared. When the player passes the UI to the next text through keystrokes, the boss changes to the roaring cut scene. In other words, I want to make a cut scene that can be controlled by UI and player input.
I don’t know how to implement it. Is there a viable way?