The Android operating system is open source, which means that any device manufacturer is free to use Android on its devices. However, Google Play is an application that is only made available to devices that pass Google’s compatibility requirements. In addition, manufacturers must obtain a license from Google in order to install the Google Play Store app on their devices.
If you don’t have the Google Play Store app app, and your device is not listed here, that means your device is not supported for use with Google Play at this time - contact your device manufacturer for additional details.