Show backspace icon in actionbar using Fragment

I am using the main activity to call my fragment but I need the icon to be implemented in actionbar of backspace.

call fragment:

getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.frameContainer, new ProvidersFragment())
                .addToBackStack(null)
                .commit();

How do I automatically open the fragment when I add my icon back to actionbar ?