The Popup Manager is a singleton component designed to manage popups across your project, with the help of Popup Contexts. It must be attached to a prefab to ensure proper behavior, and at least one instance must be placed in a scene, preferably the first scene that appears when launching your project. 

Popup Contexts allow you to set up popup parameters anywhere in your project. These parameters include a header text to clarify the popup’s purpose with a few keywords, a body text that serves as a call to action or an informative description, and one or several buttons with functions.

Note that this setup does not require you to work with any Button or Text Mesh Pro UGUI, as that is handled automatically by the Popup Manager during runtime.