This article will help you get set up with a password for your existing widget that you'd like to password-protect. Users will have to enter the password you've made in order to access this widget on your website after this is complete.
Open up a widget that you've created already.
From here, scroll down until you find the 'Privacy' section of the widget.
In the password protect column, enter your desired password in here and select save. If you'd like you can any websites you'd like to restrict the widget to access in the 'Where can this widget be embedded' column by using the URL. Example: www.google.com
Next time you open up the widget or one of your users opens up this widget they will be prompted to enter the password before having access.