Your Office 365 Home or Office 365 Personal subscription comes with 60 Skype minutes.
Skype-to-Skype calls are always free. But you can also use Skype to call mobile phones and landlines. Office 365 Home and Office 365 Personal includes 60 minutes per month of Skype calls to mobile phones in more than 8 countries and to landlines in 60+ countries (only in markets where Skype is available).
Your minutes will be automatically activated, so just dial from Skype and your friends and family can pick up on their phone. For more information, see this article.
Countries and regions you can call using Skype minutes
You can call phones around the world with your Skype minutes. See the complete list of supported destinations.
Important: Special, premium, and non-geographic numbers aren’t covered by Skype minutes. Also, it isn't possible to place emergency calls.
Calling countries and regions that aren’t included in Skype minutes
Skype offers a variety of pay-as-you-go and subscription options to supplement Skype minutes. Visit www.skype.com for more details.
If you’re already paying for Skype minutes
If you already have a Skype account, you can use it for your minutes. Skype uses your Skype minutes before any prepaid minutes.