Close apps on Android and setting reminders?

So, I'm new to android phones. I just got an android Lenovo A526. I have searched on the net but could find an option to close the apps running in background. Kindly help me out.

Also can anyone tell if there's an option to set reminders in this phone (without using internet). Should I download a app or is the option built-in.

In my Samsung tablet, you long press the home button and it pops up a screen with running apps. Tap the right hand icon and all get closed.

There are plenty of reminder apps available free in the play store. Some devices come with built-in apps, Samsung does. Not sure about Lenovo.

I'm not familiar with your phone, but there are plenty of app's that force close apps that are running in the background you might want to check that out.

As far as reminders go I personally use my calendar it's a great way to set it for daily, weekly, monthly or even yearly reminders.
Don't be afraid to experiment with your phone that's the fin part about Android phones