PC Magazine shares an informative tutorial for new iPhone users that shares the basics of all key features 

https://www.pcmag.com/article2/0,2817,2469607,00.asp

If you’ve never had a smartphone before, but just picked up an iPhone, here are all the little things you need to know.  Years ago, a friend of mine made that astronomical jump from feature phone to iPhone, and in talking to him I realized there were things I take for granted that he found completely alien. He didn’t know the difference between Wi-Fi and Bluetooth, and had no clue about the difference between Messages and Mail. Why is the web browser named Safari? Does he really need iTunes on his computer? Why on Earth would anyone talk to Siri?