A lot of the questions that get posted here can be answered by reference to the full manual for your device. I don't mean the little "Getting Started" leaflet that comes in the box and usually manages to address (um) nothing useful, I'm referring to the full monty that goes into often quite exhaustive detail.
Different manufacturers have different approaches, but they'll all have an option somwehere. The support tab on their website is a good place to start or you can turn to good old Google. Just search for "[device name] manual" and look for a site that belongs to the manufacturer themselves. There are 3rd party sites as well and these can be good for older devices, but, if yours is shiny and new, the official site is the most reliable.
The manual will be in pdf format and some have interactive indexes. Others, you just have to consult the contents and then use Acrobat's jump-to-page feature. Some are also better than others, but you should find quite lengthy explanations of all the things you can do with your phone. It's worth an extended read (OK, I'll let you skip the bits that really aren't relevant), because the chances are you'll find something you didn't even know about at all.
The manual is my first port of call for any new device and I usually put a copy on the phone itself so that I have access to it at any time. When I had my first Android phone, a Samsung Galaxy S2, the manual helped me get the email app set up right first time.
