If you have already downloaded the Skype app on your Xbox one the just login and if you don't have an account then just click create new account. If you are a active Xbox Live gold Member subscriber it will come up that you will get 100 Free minutes every month for 6 months for free. It includes mobile and landline calls to 59 Countries. It also includes free landline calls to 29 countries.
The Free Skype subscriptions end after the 6 month offer period.
100 minutes of Skype calling per month to both land lines and mobiles in
Australia, Austria, Bangladesh, Belgium, Bermuda, Brunei Darussalam, Canada, China, Columbia, Costa Rica, Cyprus, Czech Republic, Denmark, Finland, France, Germany, Greece, Guadeloupe, Guam, Hong Kong, Hungary, India, Ireland, Israel, Italy, Republic of Korea, Latvia, Lithuania, Malaysia, Malta, Martinique, Mayotte, Mexico, Netherlands, New Zealand, Northern Mariana, Norway, Poland, Portugal, Puerto Rico, Romania, American Samoa, San Marino, Singapore, Spain, Sweden, Thailand, United Kingdom, United States, Venezuela, and United States Virgin Islands; and calls to landlines in Andorra, Argentina, Brazil, Bulgaria, Chile, Croatia, Dominican Republic, Estonia, French Guiana, Gibraltar, Iceland, Indonesia, Japan, Kazakhstan, Kuwait, Luxembourg, Mongolia, Morocco, Panama, Paraguay, Peru, Russia, Slovakia, Slovenia, South Africa, Switzerland, Taiwan, Turkey and Uruguay.
**Excludes special, premium and non-geographic numbers.
Enjoy...