if you want to play this smoothly, you need to use a device/PC with at least dual-core processor.You have to update your player to latest version. Also if you use your PC to watch it, installing LAV Filter will help you a lot if you want to use KMPlayer or PotPlayer. Many updated players have native support for the codec.
If your Device doesn’t support x265 you can try updating your firmware or you can hook your Laptop or x265 compatible device to the TV with HDMI or Wireless connection and stream the video.
For PC :-
LAV Filters – https://github.com/Nevcairiel/LAVFilters/releases
For Android :-