Tap on the "Talk & Type to Siri" entry and choose "Off" and then toggle "Press Side Button for Siri" off too. You can also ...
You can easily change the voice on your iPhone for features like Siri and VoiceOver. Here's how to do it.
You can turn off VoiceOver on your iPad through the Settings app. You can also ask Siri to turn it off, or use Accessibility shortcuts.