This will depend on your device and if the new software update for Android is compatible with your device. Some older model of Android phones or tables can't be updated to the latest version of the Android software.
If your phone is compatible, all you need to do is go to your setting on the device and check to see if there are any updates.
If you are wanting to delete Android off your device this isn't possible. The device needs an OS to operate and the type of device you own will determine the OS it uses. For example, an Apple phone can't install an Android program, the chipset and phone aren't configured to run with Android software. The same holds true for all Android devices. You can only use Android software on your phone.