Hello, I would like to ask how to download or update iOS 8 -9. Help me please
You cannot download individual iOS. If you are attempting to update a device, it will download and install the latest iOS that is compatible with the device. You do not indicate what device, however given your question, I'm guessing that you may have an iPhone 4, which cannot run anything higher than iOS 7.1.2.
If you are asking something else, please provide additional details.