As a part of the Google Home app's features, you'll be able to use your Android phone as a remote control for your Android TV.
To enable this feature, ensure the TV's system app; "Android TV Remote Service" is updated on the TV's Google Play Store app.
On your phone, go to Google Play Store and download the Google Home app. If Google Home app is already downloaded on you device, please ensure it is the latest version by checking for updates in Google Play store.
On the app's home page, select your PRISM+TV's name under "Other cast devices".
Input the pairing code that will be shown on the TV screen.
Once done, you'll now be able to use your phone as a remote control.