Access "Touch ID & Passcode" from the iPhone's "Settings" menu.
Type the password you use to lock the screen. Look for a setting that says "Turn Passcode Off" at the bottom of the screen. Select that one.
The third step is to confirm the disabling of your password in the pop-up window that appears. To disable the iPhone screen, tap the "Turn Off" button.
You will need your original password to disable the password. Input the original password, and you're good to go.
Once you disable the password, you won't need to use it again.