how do i delete this feature off my phone?

If you mean Switch Control, you can't delete the feature from your phone. However, you can turn it off by going to Settings>Accessiblity>Switch Control. It's also possible that you have the Accessibility Shortcut set up to enable that. If so, try triple-clicking the Side Button to turn it off. You can disable the Accessibility Shortcut in Settings>Accessibility>Accessibility Shortcut.

If you mean something else, please explain.

Delete what function?