Plain white studio
A seamless white backdrop with soft, even light.
Keep the same person or subject, their face, clothing, body movement and timing, and the camera movement of the source video exactly the same. Change only the background behind the subject. Replace it with a seamless white photography studio backdrop, softly and evenly lit, with a subtle floor shadow under the subject. Match the lighting on the subject to the new background. Do not add text, logos or watermarks.
Works best when the subject stands apart from the wall.