Is there any guide to all the settings on the iPhone?

I

iMore Question

I would like to know what all the settings do in the iPhone (new to Apple)
i know most of them are self explanatory, but others not so much.

There are a number that I really have no idea how they should be set... One example would be Wallet - It defaults to having location service on, but why would it need it? What would be the affect if I turned it off?

There are a number of others as well. Would just like to know what best settings (or what they at least mean would be).

One bonus question, I upgraded to iOS9 when I swipe to the left of home screen where are those news feeds coming from and can I edit them? I have not touched or setup News yet.

Thank you