The dongle only needs power from the USB socket, you connect to it by following the instructions and finding it just like you would a WiFi router at home or a WiFi Hotspot, so yes, just plug it into the Surface USB socket.
Please be aware that you require a mobile phone SIM that you put into the dongle to get Internet - this can be an existing SIM from your phone (but you may need an adapter as this takes "full size" SIMs, not "mini" or "midi" or buy a new dedicated SIM card for it. Be also aware of roaming charges if you are going to a place outside the country where you bought the SIM.
Hi Duncan. It does not require a sim that allows tethering. This is a great device. I insert my sim from my 3 dongle, insert it into my phones 3 pin plug and once it is switched on, my phone, tablet and laptop recognise it as a wifi hotspot. It will ask for a password which is the number located near the sim insertion. You only need toenter this password once for each device and away you go. Hope this helps?
I can't answer for the surface 2 specifically, but it provides a standard secure wifi hotspot when fitted with a 3G sim card with suitable data package, plugged in to any suitable USB power supply and obviously within range of the 3G data transmission. I hope that helps.