I'm not sure what you mean when you say you "DL GPS" to your tablet. The tablet already has the GPS hardware built into it. Are you saying you're trying to download a navigation app? If so, which app are you trying to download and install?
On Android, all of your apps will show in the App Drawer, there's generally an icon on the Home screen you can click that will open the App Drawer and show you all the apps you have installed on the device.
That stuff about not using a GPS indoors or it will ruin it is totally bogus and complete nonsense. While it's true that a gps receiver used indoors may not be able to obtain a fix and will search continuously, it certainly will not damage the receiver.
I have used various gps receivers indoors (including several Garmin units that I have owned) and sometimes coud get a fix and other times I couldn't but no damage occurred to the receiver.