For Skype for Business Online organizations, you can use the Remote PowerShell in Office 365 to enable your Skype for Business users to use the Skype for Business client or the Skype for Business (Lync) client user interface. The default setting is for users to use the Skype for Business client user interface.
Yes you do - all of it, but under most circumstances, not until after you graduate college (or leave school for other reasons). Under normal circumstances when you graduate or drop below a certain # of units of attendance, you will be expected to begin paying back your student loan 6 months later. For subsidized student loans, this is when the interest will start accruing as well.
From experience he will probably not pay for it. But you need to wait 7 days and start an unpaid item claim for it. After it has been started you need to wait another 7 days to finalize it and get your fees back - then relist. If you relist before then they can pay for the item and you will be stuck in a big mess.