You need to download Pages from the Mac App Store. Once installed, make sure Documents and Data is check marked in System Preferences/iCloud.
Then on your iPad, turn on Pages in Settings/iCloud and that should be it. Both apps need to be downloaded using the same AppleID, and obviously both devices need an Internet connection.
If all goes well, documents should automatically sync between the two devices. If you gave an iPhone, you can install Pages on that for free, since its the same app as the iPad version.