Here is a concise, straightforward explanation of how to update your Apple devices.
On iPhone or iPad
1. Tap Settings > General > Software Update2. Tap Automatic Updates, then toggle Download iOSUpdates and Install iOS Updates
On Apple Watch
1. Open the Apple Watch app2. Tap the My Watch tab, then General > Software Update3. Tap on the update and follow the prompts
On Mac
1. Click on the Apple icon in the corner of your screen, then choose System Preferences2. From the System Preferences window, click Software Update3. Depending on whether it's a minor or major update, click on Update Now or Upgrade Now
On Apple TV
1. Open the Settings app on Apple TV and select System > Software Updates2. Select Update Software and follow the prompts