Finding an Android app's package name and Activity

1. Open play.google.com in your web browser.
2. Use the search bar to look for the app for which you need the package name.
3. Open the app page and look at the URL. The package name forms the end part of the URL (i.e. after the id=?).
4. Copy it and use it as needed.
   Source: https://www.techmesto.com/find-android-app-package-name/

You can also use Appium Desktop to retrieve the App Package and Activity for Android.

1. Open Appium Desktop
2. Start the session and app
3. Go to the actions tab, see image 1
4. Select Device from the first drop-down
5. Select Android Activity from the second drop-down and you will get a screen like in image 2
6. Click the buttons and you will get the data as in image 3