Can I Attach a Keyboard or Pair a Mouse?
No. But you can use any bluetooth or USB receiver-based wireless keyboard and mouse. When doing this, your iPad Pro must be updated to iPadOS 14 to enable mouse and keyboard support.
Can I Plug the Hub in a MacBook Pro to Charge It?
While this is designed for the iPad Pro, the base technically can plug into the charge port for your MacBook Pro and act as a backup power source, so long as the port is a USB-C port.