SETTINGS app has disappeared from new iPad

My son gave me his old iPad and in trying to move my apps from my v.5.1.1. to the new iPad (v. 8?) All the apps he had put on it including SETTINGS disappeared!!

I am lost!

I think if I could figure out a way to add the second iPad to " devices" in iTunes, I could maybe restore SETTINGS from there??

any ideas PLEASE.

Thanks

Glen