Open the Photos app
Select the picture
Tap Edit
Use the adjustment tools to reduce sharpness if available
Use Markup to draw over parts if needed
Use a third-party app like Snapseed, Canva, or Photoshop Express for stronger blur effects
Open the app and import the photo
Choose the Blur, Lens Blur, or Selective Blur tool
Apply the blur to the desired area
Save the edited photo
For portrait photos, use Portrait mode photos with background blur already applied
For screenshots or sensitive info, use the Markup tool to cover text before sharing