Your contacts and contact groups in Skype for Business will be migrated to Teams on the migration day. Microsoft is working on 'Public Skype' and Teams interoperability, although we don’t have exact date for this feature.
Select Join or create team > Create a new team. Upcoming Microsoft Teams Instructor-Led event that you may find useful. Note Newly created teams can be managed right away in the Teams Admin Center, unlike the experience in other clients like, Outlook. Empowers you to create, collaborate, and innovate through a host of email.
Each Team shares the similar makeup of channels, posts, and files. Groups, is the first attempt by Microsoft to create a true collaboration tool that spans multiple services and components within Office 365.