Cut out the subject, then try tan, coffee or chocolate brown behind it. Preview live and download a JPG.

Brown feels natural and warm. It suits coffee, leather, ceramics, wood goods and anything sold on craft and sustainability. Cream, white and green items have the strongest contrast.
Tan (around #b08968) is soft and neutral. Coffee (around #6f4e37) is warm and balanced. Chocolate (around #78452a) is deep and works for light and bright products.
Leather, wood and cardboard items blend into a similar brown. Use a cream, sage or teal background for those, and keep brown for white, green and metallic products.
Pick any shade in the Change Background Color tool, or start from a color below. Marketplace main images usually need pure white, so use the white background tool for those.
Upload the photo, wait for the cutout, then choose a brown shade with the color picker or enter a hex code. Download a JPG.