When you're in a Skype call on a Surface Hub, you can get to meeting content from the Content pane. Here are some of the things you might find there:
The invitation for a scheduled meeting (including the body text), any links to content, and a link to join the Skype for Business meeting (if the original invitation included one).
A list of people in the meeting who are sharing their screens (to bring someone's screen to the front of the stage when they are on the call but not in the meeting room, select their name from the list).
PowerPoint files that are currently being presented in the Skype for Business meeting (select a file to bring the presentation to the front of the stage).
You might be asked for a PIN to access meeting content. If so, select Need a content PIN? Select the person you want to send the PIN to, and then select Send.
The person can then type the PIN and select OK to access the meeting content.