TalkBack screen reader provides you verbal feedback and notifications.
To turn on TalkBack:
1. Press both volume keys:
Important: The first time you use this option on your device, you will be asked if you want to turn on the volume keys shortcut. You can select Turn On to confirm, or press and hold both volume keys again for a few seconds.
Hold down both volume keys for a few seconds.
2.Open TalkBack in the Settings of your device:
The steps below require visual assistance.
Open your device’s Settings app.
Select Accessibility, then TalkBack.
Select Use TalkBack.
Tap OK in the confirmation dialog.
Optional: Change the TalkBack shortcut.
You can check the link for more detailed information.