Open Safari or Chrome on your iPhone
Go to images.google.com
Tap the camera or Google Lens icon
Upload the image from your Photos app
Or paste the image URL if you have one
Wait for Google to show matching or similar images
Use the results to identify the source or related pages
Open the Google app and tap the Lens icon for another option
Take a new photo or choose one from your gallery
Review the visual matches and search results
Use TinEye in Safari if you want a different reverse image search tool
Upload the image on TinEye and view the matches
Use the Photos app to copy an image and search it in supported apps
If the image is in Messages or Mail, save it to Photos first
Try different apps or browsers if one method does not work