It is not possible to completely remove those fields; you can only change the text labels for them. As you can see, they already have "placeholder" text indicating they are optional, so most buyers correctly understand that to mean they can leave those fields unfilled.
If your test orders are requiring you to enter a Phone, make sure you untick Require buyer phone number in your E-junkie Dashboard under Manage Seller Account > Edit Preferences (near the bottom of that screen).
