Don't worry, @VirginiaAnn we all start someplace.

Task managers, task killers, battery optimizers or whatever you want to call them are all utilities that promise to make your phone run better. They don't. In fact many times then make your phone run slower and run the battery down quicker. The worst kinds are security risks, so we don't recommend using them. There are a few legitimate reasons for them, but they are rare.

(I see I just got ninja'ed by @El Presidente )

Instead of focusing on tools that aren't going to fix your problem, let's work to fix your problem. Could you let us know what phone you have? Do know what version of Android it runs? Don't worry if you don't.

You say your battery is draining quickly. If you go to menu>settings>battery, you should see a graph of your battery drain and what apps are using the most power. Let us know that and we help you better.

By the way, Android is designed to use most of your memory and keep apps loaded as much as possible. It's actually a more efficient way of running an OS, but it seems counter-intuitive if all you know is Windows.

As for ES File Explorer, that just is a file manager that lets you look at individual files like you can on a PC. Was there something you specifically wanted to do with your files? Most people don't really need an advanced file manager like ES.

 

The Zmax is a pretty big phone and the bigger the screen the more power it's going to use. It shipped with Android 6.x (Marshmallow) but it might have upgraded to 7 (Nougat), but I couldn't say for sure. 10% in 30 minutes doesn't seem excessive if you are watching movies or reading with the screen on a moderate to high level of brightness. It does have a 3400mA battery so you should see decent performance.

You might consider that if it's a new phone, you are using it a bit more than you might once you get familiar with it. Also, because it's new, it might actually be reporting the power usages incorrectly. Normally it takes several weeks of use for a phone to calibrate the power consumption and show you a more accurate picture of your battery drain.

Okay, let's talk about apps running. I assume you are looking at menu>settings>applications and see all the apps listed under the 'running' tab. Trust me, they aren't all running ... and by running I mean using processor cycles and consuming battery power. What see are apps that are basically put in a standby state in your active memory and are ready to run when you actually tap on their icons.

To see what is actually using your power, go to menu>settings>battery and tell us what you see.

 

I hate to tell you this, but that all looks pretty good to me. I see that from your battery chart that you took the phone off the charger at 11:00 a.m. at 100% and by 6:00 a.m. the next day it's down to 15% or 20% with the screen using 25% of the power consumed. As I said before, the screen -- especially a bigger screen -- uses a lot of juice.

The apps themselves aren't using loads of power or they'd be in your list. Cell standby, phone idle, calls ... that's what's using your power and you can't really shut them off or your phone wouldn't work at all.

Now, if something has changed recently where you used to get much longer use times, then we can look for that, but if this has been like this since you've owned it, then it seems pretty reasonable. Maybe you could charge it more frequently? You don't have to wait to charge it. Modern batteries do better with more incremental charges that one lone one daily.

 

Then that's even better. It started at less than 100% and lasted almost a full day. With a large screen phone, that's pretty good.

Actually they do as soon as you stop using them. They are still listed under apps, but they aren't using your battery or you would see them under the battery chart.

And this is where most users get into trouble. trying to 'stop' these apps actually forced Android to restart them to put them back into memory. This extra activity is additional battery drain. I hate to tell you this but everything you've been told about task managers is actually contributing to your battery drain rather than helping.

I'd recommend getting rid of all the task managers and turning down your screen brightness a bit.

 

I could repeat or restate a lot of what's been said, but I won't. I'll simply make two points:

1. Android manages resources just fine and task managers normally do more harm than good.
2. You are being helped by @El Presidente and @lunatic59, two of the finest and most helpful members and mods here, so heed their advice. Ask as many questions you need until you understand, and do our best to help you figure it out. See point one, that's what you need to understand.