Open the Photos app
Select the photo you want to edit
Tap Edit
Use the Markup tool or a background removal app if needed
Open a background editing app from the App Store if the Photos app does not support full background change
Remove the original background using the app’s cutout or erase tool
Choose a new background image or color
Place the subject onto the new background
Adjust size, position, and edges
Save the edited photo
Export or share the final image