In this episode, Tyler demonstrates how to disable predictive text suggestions on macOS.
As you type on your Mac, macOS by default attempts to finish words and phrases it thinks you're trying to type. If you find that hearing these suggestions spoken by VoiceOver is more distracting than helpful, you can turn them off by going to System Settings > Keyboard, clicking the Edit button under the "Text input" heading, and toggling the "show inline predictive text" switch off.