Hi Bearcat6690. I am like you and would prefer a paper manual and I agree that as costly as a smart phone is a manual should come with the device. But as Meg mentioned, Apple (And almost every other tech manufacturer) has determined that it would be very costly to include a hard copy manual. They have also discovered that you and I are in the minority anymore when it comes to manuals like this. (I just bought a new car and had to download the owners manual as a pdf. A $35,000 car doesn't include a manual any more.) So they leave it up to the buyer to take the time to locate and download a soft copy manual. I just keep a copy in iBooks on both my iPhone and iPad.
But to be honest I rarely open it anymore. I have found that simply digging into the apps, settings, touching icons within apps, and generally playing with it as much as I can for awhile really helped me learn more about my phone and it also helped me customize it to my personal tastes.
If there is something that I can't figure out by digging into my phone myself or trying to find it in the manual, I come here and always find someone who has had the same problem and is happy to help me out.
Regarding battery life, the apps that are in the multitasking drawer are (for the most part) just waiting to be opened again. In fact by leaving them in the multitasking drawer and not shutting them down you end up using less power because it takes longer to restart them if you close them down. When you close an app the phone takes a snapshot of its last state and keeps that information handy so that when you open the app again it will open to where you were. The exception to this would be apps that actually do run in the background such as maps or apps that use GPS. But you can turn that off as well in Settings > General > Background App Refresh and turning off the apps you don't want to run in the background, or toggle this feature off all together. You will notice that the apps that appear in this setting are the ones that use GPS or need to update themselves from other apps, such as your calendar.
If you use a lot of apps and switch between them a lot and you feel your phone is starting to get sluggish that is when you want to go in and close down some of the apps in the multitasking drawer. The snapshots do take up a little bit of memory and that will eventually start to slow things down. But they don't draw any power just sitting there. If you find that closing apps does help your battery life you may be closing down the few apps that are actually doing something in the background.
I also turn ON Settings > Privacy > Advertising > Limit Ad Tracking. This one doesn't get brought up much, but it is a battery drain as well.
And I strongly suggest that you set email to manually fetch when you open the Mail App rather than setting it to push so that your mail is automatically pushed to your phone. Pull mail is a real battery killer because it needs to wake your phone up every 15 minutes or so and ping your mail server(s).
Good luck with your phone and I hope you get to enjoy it and get as much use out of it as I do.