backup your iPhone to iCloud, Follow these steps:
1. Connect to Wi-Fi: Make certain your iPhone is connected to a stable Wi-Fi network.
2. Open Settings: Go to the Home display screen and faucet on the Settings app (the tools icon).
3. Tap Your Apple ID: Follow the Settings menu,
4. Access iCloud Settings: Tap on iCloud.
5. Go to iCloud Backup: Scroll down and faucet on iCloud Backup.