How to disable my home buttonn

The Home button, is a primary button and cannot be disabled per se. There are accessibility options though, which can modify the default operation of the said button. Look here: About the Accessibility Shortcut for iPhone, iPad, and iPod touch - Apple Support

Use the Home button 

• To set up Accessibility Shortcut: Go to Settings > Accessibility > Accessibility Shortcut, then select the features that you use the most.
• To use Accessibility Shortcut: Triple-click the Home button.
• To slow down the double-click or triple-click speed for the Home button: Go to Settings > Accessibility > Home Button, then change the setting.