Thank you for reaching out, I can understand wanting to have a downloaded app on the home screen. You can add an app on your phone from your home screen, you can do so by doing the following:
From the home screen you would like to add the app on, swipe up on the screen to pull up a list of all the app downloaded on the phone.
Find the app you would like to add to the home screen
Tap and hold on the app until it is floating over the home screen and drag the app to where you would like to place it.
Let me know if this helped!