This plugin adds Authy two-factor authentication to WordPress.
The user should go to his or her WordPress profile page and add his or her mobile number and country code.
The user should return to his or her WordPress profile screen and disable Authy at the bottom.
Yes, as an admin you can go to the settings page of the plugin, select the user roles in the list, and click "Save Changes" to save the configuration.
As an admin, you can go to the users page. Then, select the user in the list, and click edit. Go to the bottom, enter the user's mobile number and country code, and click "Update user."