First, they must both be using the same iCloud account under Settings > iCloud. That will take care of everything listed under those settings.
Other services like Music, iBooks, Podcasts, Photos, etc. Have their individual sync settings.
Services like iCloud Photo Library and iTunes Match may require you to purchase more than the free 5GB of iCloud service before they will work.
Additionally your Phone, Messages, and FaceTime settings have indivudual settings that can be different from your main iCloud settings. When you initially set up an iOS device with an iCloud account they should have been automatically added, but if you have to change the account for any reason then these apps will have to be manually signed out of and back into.
Pay special attention to the Phone and Messages setting son the iPhone. This where you'll enable phone call and SMS message abilites on the iPad.