Yes I think you got an original unit
It is and was never intended to be a cellphone (you should have looked at the spec before buying ).

Glad you found a working solution for your Skype problem.
As for the GPS you should do nothing to configure it, just run a GPS application and it will work out of the box.
Only remember that the first FIX will take plenty of time (can be up to several minutes) and should be done outside a building with a clear view of the sky.
After the first FIX, the next fixes should be faster.

The tablet CAN guide you from one place to the other, but, for that you have to pay Wayfinder (it's cheap).
If you don't pay you can still use the Map application. It will tell you where you are and what's around you.
There should be a 7-day long evaluation period you could try, but if you bought it used off eBay, probably the first owner used it already.

You can indeed download maps for other countries, just go to the Map application and dig into the "Map" entry of the menu.
You can also download different voices even in different languages.

You're welcome