Even though that is a really easy task, everyone get confused becase there are lots of different things are said on the internet. I’m assuming that you’ve already downloaded and installed Android SDK’s.
So firstly to start your emulator:
Go to the folder -> android-sdks -> tools
And run this command ./android
Now you’ll have just started Android SDK Manager, now from the top menu click Tools -> Manage AVDs. You can see your android devices, add, delete or edit devices. Click on the device that you want to start and click “Start”
To test that this emulator is active now go to the folder -> android-sdks -> platform-tools
And run this command ./adb devices
It will show that:
List of devices attached
Now you’re ready to install your .apk file into your Android Emulator
Run this command and you’re ready to test your application !
./adb install “YOUR APPLICATION.apk”