To check for available updates over-the-air (OTA update):

1.- Make sure your device is connected to Wi-Fi.

2.- Open the Settings application.

3.- Select About phone-Wireless update

4.- Click on Check update​

It will show, if your system up-to-date 

5.- The System Update will be installed.
Depending on the operating system, you will see Install Now, Restart and Install, or Install System Software. Click. The phone will reboot.