Syncing iPad and iphone

Click on this link to learn how to 'Set up iCloud on your iPhone, iPad, or iPod touch' --> https://support.apple.com/HT208681

Make sure you turn on iCloud for whatever services you can.

Change your iCloud feature settings [iOS and Mac] - hhttps://support.apple.com/HT207689

For some things such as media you either have to use a syncing services such as Apple Music or Match, or you have to sync both devices to the same computer.

Turn on Sync Library [formerly iCloud Music Library] with Apple Musichttps://support.apple.com/HT204926

Are you talking about syncing them to a computer or syncing them together? If you are talking about syncing them together, you cannot do this. You can use some settings with iCloud to make settings and things sync between them, but you can not directly sync them together.