Connect your iPhone to your computer with a USB cable
On a Mac with macOS Catalina or later, open Finder
On a Mac with macOS Mojave or earlier, open iTunes
On a Windows PC, open iTunes
Select your iPhone when it appears
Click Trust on your iPhone if prompted
Click Back Up Now
Choose Encrypt local backup if you want to save passwords and Health data
Wait for the backup to finish
Check the latest backup date and time to confirm it completed
Eject your iPhone safely and disconnect the cable