Use an online background remover tool
Upload the image
Let the tool detect the subject
Refine the selection if needed
Download the image with a transparent background
Use photo editing software like Photoshop, GIMP, or Photopea
Select the subject with a selection tool
Invert the selection to target the background
Delete the background or mask it out
Export the image as a PNG file
Use mobile apps with background removal features
Save the edited image in a format that supports transparency