This wikiHow will show you how to install the latest Apple operating system on your iPhone or iPad.
Steps
Method 1 of 2: Using an iPhone or iPad

Step 1. Open "Settings"
The settings icon looks like a gray gear (⚙️) and is usually located on the home screen of your device.

Step 2. Scroll down and tap on "General"
It's at the top of the menu, opposite the gear icon (⚙️).

Step 3. Select "Software Update"
It's at the top of the menu.

Step 4. Click Install Now
If a software update is available, you will see an Install Now button below the update description.

Step 5. Enter your password
Enter the password you use to unlock your phone.
- The update process for your phone will start.
- In some cases, you may need to set up your phone again, but applications and all data should remain intact.
Method 2 of 2: Using iTunes

Step 1. Connect your iPhone or iPad to your computer
Use the original USB cable that came with your device.
- Click the button Trustwhich will appear on the screen of your phone after it is connected to the computer.

Step 2. Open iTunes
Usually, iTunes will launch automatically when you connect your device.

Step 3. Click on the device icon in the top menu of the application window
The icon may not appear immediately.

Step 4. Click on Create Backup
Before updating the OS, it is advisable to create a backup in case something goes wrong. This process takes only one to two minutes, and it allows you to restore your iOS device if an error occurs during the update process. Step 5. Click on Check for Updates.
You will see this button on the Summary page after you select your iOS device.
The first time you launch iTunes with a device connected, you may be prompted to update the device automatically. You will see this message if the device OS has already been updated to the latest available version

Step 6. Click Download and Update
This will download the updates to your computer and install them on your iOS device. The whole process may take some time. You will be able to track it on the screen of your mobile device.

Step 7. Finish the update process
Once the update is installed on your iPhone, iPad, or iPod, you'll need to complete the process by entering your password or signing in with your Apple ID.