How to download the .apk file (new version of the program) and open the installer in Android when a pop-up window is clicked and clicked "OK"?

Question

Android

The application checks if there is an updated version, displays a message to the user "A new version has been released", how when I click "Update" I will automatically start downloading the .apk file from my server so that the user can see it and then start installing the file or stay in the window so that he himself on it pressed.
How do they do things like this?

Answer 1